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No watches are valid as of Mon Apr 17 21:31:01 UTC 2023.

No Mesoscale Discussions are in effect as of Mon Apr 17 21:31:01 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Mon Apr 17 2023 Valid 172000Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe wind gusts and small to marginally severe hail will be possible between 4 to 9 PM CDT across parts of west Texas and southeast New Mexico. ...Discussion... The only change made to the previous convective outlook is to remove low-severe probabilities over South FL. Convective overturning coupled with veering low-level flow --coincident with a cool front-- will combine to diminish the risk for severe thunderstorms the remainder of the afternoon. ..Smith.. 04/17/2023 .PREV DISCUSSION... /ISSUED 1123 AM CDT Mon Apr 17 2023/ ...Southeast FL... A near-term threat for a severe storm or two should persist for a couple more hours attendant to a minor southern-stream mid-level trough passing across the southern peninsula. Within a lingering combination of moderate buoyancy and deep-layer shear, weak supercells will remain capable of producing small to marginally severe hail and locally strong gusts. Low-level winds appear to be in the process of weakening and becoming more veered, which will result in a decreasing threat later this afternoon. ...West TX and southeast NM... Northwest of the more substantial moisture return, deep boundary-layer mixing will support at least isolated high-based thunderstorms along a lee trough during the late afternoon and early evening. Inverted-v thermodynamic profiles with DCAPE of 1000-1500 J/kg will favor strong to locally severe outflow gusts with semi-organized cells, based on the steep lapse rates and moderately elongated, straight hodographs. An LP-supercell with a marginal hail threat is plausible towards the Big Bend/Lower Pecos Valley owing to greater elongation of the hodograph and MLCAPE near 500 J/kg. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Mon Apr 17 2023 Valid 172000Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe wind gusts and small to marginally severe hail will be possible between 4 to 9 PM CDT across parts of west Texas and southeast New Mexico. ...Discussion... The only change made to the previous convective outlook is to remove low-severe probabilities over South FL. Convective overturning coupled with veering low-level flow --coincident with a cool front-- will combine to diminish the risk for severe thunderstorms the remainder of the afternoon. ..Smith.. 04/17/2023 .PREV DISCUSSION... /ISSUED 1123 AM CDT Mon Apr 17 2023/ ...Southeast FL... A near-term threat for a severe storm or two should persist for a couple more hours attendant to a minor southern-stream mid-level trough passing across the southern peninsula. Within a lingering combination of moderate buoyancy and deep-layer shear, weak supercells will remain capable of producing small to marginally severe hail and locally strong gusts. Low-level winds appear to be in the process of weakening and becoming more veered, which will result in a decreasing threat later this afternoon. ...West TX and southeast NM... Northwest of the more substantial moisture return, deep boundary-layer mixing will support at least isolated high-based thunderstorms along a lee trough during the late afternoon and early evening. Inverted-v thermodynamic profiles with DCAPE of 1000-1500 J/kg will favor strong to locally severe outflow gusts with semi-organized cells, based on the steep lapse rates and moderately elongated, straight hodographs. An LP-supercell with a marginal hail threat is plausible towards the Big Bend/Lower Pecos Valley owing to greater elongation of the hodograph and MLCAPE near 500 J/kg. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0216 PM CDT Mon Apr 17 2023 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR MUCH OF NEW MEXICO INTO PORTIONS OF THE SOUTHERN AND CENTRAL HIGH PLAINS.... ...New Mexico and the southern/central High Plains... Widespread critical fire-weather conditions are expected D2/Tuesday ahead of the approaching upper trough and strong mid-level flow. A sharpening dryline will support west/southwest surface winds of 20-25 mph within areas of RH below 15% from central and eastern NM into west TX. Farther north across the central High Plains, widespread critical fire-weather conditions are also expected. Despite some areas of wetting precipitation over the past 72 hours, rapid drying and strong downslope flow over the Rockies will support RH values below 15% with winds gust 20-25 mph. Less confidence in fuels exists farther north and east across portions of CO and NE given locally heavier precipitation. However, the strong winds and low humidity post dryline will likely still support a risk for critical fire-weather Tuesday afternoon. ..Lyons.. 04/17/2023 .PREV DISCUSSION... /ISSUED 0210 AM CDT Mon Apr 17 2023/ ...Synopsis... A mid-level trough will impinge on the Plains states tomorrow/Tuesday, resulting in surface low development and associated dry downslope flow across the central and southern High Plains. Widespread Elevated conditions are likely throughout the southern and central High Plains, with Critical highlights added where winds are expected to exceed 20 mph amid 10-15 percent RH and dry fuels. A mid-level trough and associated surface low will continue to drift away from the East Coast, though dry and breezy conditions should linger east of the Appalachians. Guidance consensus depicts 15+ mph sustained westerly surface winds overlapping 15-25 percent RH for at least a few hours Tuesday afternoon across southern VA. Fuels in the area are relatively dry despite green-up (given an ongoing drought). Elevated highlights have been added where the aforementioned dry and windy surface conditions overlap with fuels that have not experienced appreciable rainfall in the past week. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0216 PM CDT Mon Apr 17 2023 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR MUCH OF NEW MEXICO INTO PORTIONS OF THE SOUTHERN AND CENTRAL HIGH PLAINS.... ...New Mexico and the southern/central High Plains... Widespread critical fire-weather conditions are expected D2/Tuesday ahead of the approaching upper trough and strong mid-level flow. A sharpening dryline will support west/southwest surface winds of 20-25 mph within areas of RH below 15% from central and eastern NM into west TX. Farther north across the central High Plains, widespread critical fire-weather conditions are also expected. Despite some areas of wetting precipitation over the past 72 hours, rapid drying and strong downslope flow over the Rockies will support RH values below 15% with winds gust 20-25 mph. Less confidence in fuels exists farther north and east across portions of CO and NE given locally heavier precipitation. However, the strong winds and low humidity post dryline will likely still support a risk for critical fire-weather Tuesday afternoon. ..Lyons.. 04/17/2023 .PREV DISCUSSION... /ISSUED 0210 AM CDT Mon Apr 17 2023/ ...Synopsis... A mid-level trough will impinge on the Plains states tomorrow/Tuesday, resulting in surface low development and associated dry downslope flow across the central and southern High Plains. Widespread Elevated conditions are likely throughout the southern and central High Plains, with Critical highlights added where winds are expected to exceed 20 mph amid 10-15 percent RH and dry fuels. A mid-level trough and associated surface low will continue to drift away from the East Coast, though dry and breezy conditions should linger east of the Appalachians. Guidance consensus depicts 15+ mph sustained westerly surface winds overlapping 15-25 percent RH for at least a few hours Tuesday afternoon across southern VA. Fuels in the area are relatively dry despite green-up (given an ongoing drought). Elevated highlights have been added where the aforementioned dry and windy surface conditions overlap with fuels that have not experienced appreciable rainfall in the past week. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 0552 CONCERNING HEAVY SNOW FOR PORTIONS OF NORTHERN WISCONSIN AND LAKE SUPERIOR
Mesoscale Discussion 0552 NWS Storm Prediction Center Norman OK 0125 PM CDT Mon Apr 17 2023 Areas affected...Portions of northern Wisconsin and Lake Superior Concerning...Heavy snow Valid 171825Z - 172130Z SUMMARY...Heavy snowfall with rates 1-2 inches per hour expected to continue through late afternoon. DISCUSSION...A band of moderate to heavy snow continues across portions of Lake Superior and northern Wisconsin behind a strong surface low and evident TROWAL. Northwesterly flow across Lake Superior has led to a band of locally very heavy snow, with mesoscale enhancement from moisture fetch across the lake and upslope flow. 1.5-2"/hr rates have been observed within this bad. Hi-res ensemble guidance indicates that 1-2"/hr rates could continue over the next couple of hours. Expect quick accumulations with periods of reduced visibility, as winds gusts up to 25-30 mph are also being observed. ..Thornton/Grams.. 04/17/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DLH... LAT...LON 46559201 47009160 47179132 47459097 47669053 47609044 47449061 47289069 47119082 46939097 46799108 46649111 46459117 46319131 46299173 46389194 46559201 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1223 PM CDT Mon Apr 17 2023 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN AND CENTRAL GREAT PLAINS STATES WESTWARD INTO WYOMING... ...SUMMARY... Isolated severe thunderstorms are possible from parts of the southern Great Plains northward into the Mid Missouri Valley and westward into Wyoming. Severe gusts and large hail will be the hazards with the stronger storms Tuesday afternoon into Tuesday night. ...Synopsis... A large-scale mid-level trough will be situated over the northwest part of the Lower 48 states on Tuesday. A mid-level speed max initially over the Sierra Nevada will quickly move through the base of the trough and reach the Dakotas by daybreak Wednesday. In the low levels, surface high pressure will reside over the Southeast while a surface trough/dryline sharpens over the Great Plains and induces strengthening southerly low level flow over the central-southern High Plains. A surface low will gradually deepen and migrate to the western Dakotas from WY during the period. ...Central-Southern Great Plains into WY... Southerly low-level flow will advect the initial stage of moisture return northward from the southern Great Plains into the central Great Plains during the day. Strong heating near the dryline/surface trough over western KS will result in very steep low-level lapse rates and deeply mixed profiles on the north periphery of 50s dewpoints. By mid afternoon, 1500-2000 J/kg SBCAPE is forecast from western KS southward into northwest TX. Strongly veering flow in the low to mid levels will result in 30-40 kt effective shear. Although moisture will be marginal, localized erosion of the cap is expected with isolated to widely scattered storms possible. Farther south over western OK/northwest TX, widely spaced and lower thunderstorm coverage is expected. Farther northwest over central WY, the arrival of the speed max during the afternoon within a narrow plume of adequate moisture --resulting in weak surface-based buoyancy-- will favor diurnal storm development. Very steep lapse rates and strong southwesterly low to mid-level flow will favor isolated severe gusts with the larger cores. Additional storms and some increase in storm coverage may occur by early evening towards the SD/WY border. Isolated severe gusts/large hail are possible before this activity gradually weakens during the evening. ...Low to Mid MO Valley Tuesday night... During the evening into the overnight, a strengthening southerly LLJ and associated warm air advection will favor scattered thunderstorms developing primarily overnight on the eastern periphery of steep 700-500 mb lapse rates. A few of the stronger storms will potentially be capable of large hail given the ample cloud-layer shear and elevated buoyancy. ..Smith.. 04/17/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1223 PM CDT Mon Apr 17 2023 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN AND CENTRAL GREAT PLAINS STATES WESTWARD INTO WYOMING... ...SUMMARY... Isolated severe thunderstorms are possible from parts of the southern Great Plains northward into the Mid Missouri Valley and westward into Wyoming. Severe gusts and large hail will be the hazards with the stronger storms Tuesday afternoon into Tuesday night. ...Synopsis... A large-scale mid-level trough will be situated over the northwest part of the Lower 48 states on Tuesday. A mid-level speed max initially over the Sierra Nevada will quickly move through the base of the trough and reach the Dakotas by daybreak Wednesday. In the low levels, surface high pressure will reside over the Southeast while a surface trough/dryline sharpens over the Great Plains and induces strengthening southerly low level flow over the central-southern High Plains. A surface low will gradually deepen and migrate to the western Dakotas from WY during the period. ...Central-Southern Great Plains into WY... Southerly low-level flow will advect the initial stage of moisture return northward from the southern Great Plains into the central Great Plains during the day. Strong heating near the dryline/surface trough over western KS will result in very steep low-level lapse rates and deeply mixed profiles on the north periphery of 50s dewpoints. By mid afternoon, 1500-2000 J/kg SBCAPE is forecast from western KS southward into northwest TX. Strongly veering flow in the low to mid levels will result in 30-40 kt effective shear. Although moisture will be marginal, localized erosion of the cap is expected with isolated to widely scattered storms possible. Farther south over western OK/northwest TX, widely spaced and lower thunderstorm coverage is expected. Farther northwest over central WY, the arrival of the speed max during the afternoon within a narrow plume of adequate moisture --resulting in weak surface-based buoyancy-- will favor diurnal storm development. Very steep lapse rates and strong southwesterly low to mid-level flow will favor isolated severe gusts with the larger cores. Additional storms and some increase in storm coverage may occur by early evening towards the SD/WY border. Isolated severe gusts/large hail are possible before this activity gradually weakens during the evening. ...Low to Mid MO Valley Tuesday night... During the evening into the overnight, a strengthening southerly LLJ and associated warm air advection will favor scattered thunderstorms developing primarily overnight on the eastern periphery of steep 700-500 mb lapse rates. A few of the stronger storms will potentially be capable of large hail given the ample cloud-layer shear and elevated buoyancy. ..Smith.. 04/17/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1154 AM CDT Mon Apr 17 2023 Valid 171700Z - 181200Z The previous forecast remains valid with only minor adjustments for the latest guidance. Isolated dry thunderstorms are expected over portions of the southern High Plains along with gusty winds and low humidity. Locally elevated fire-weather conditions are also possible across the eastern US, but confidence remains too low to add an Elevated area given widespread wetting rain. Please see the previous discussion for more information. ..Lyons.. 04/17/2023 .PREV DISCUSSION... /ISSUED 0209 AM CDT Mon Apr 17 2023/ ...Synopsis... A mid-level ridge will overspread the Plains states as an upper trough pivots toward New England. A departing surface low will encourage broad, dry westerly surface winds across much of the OH/TN Valleys and points eastward. Surface lee troughing across the southern High Plains will also develop by afternoon peak heating, encouraging both dry/windy surface conditions, and isolated dry thunderstorm development. ...Southern High Plains... By afternoon peak heating, 15 mph sustained southerly surface winds overlapping 15-20 percent RH are likely across portions of northeast NM into the TX and OK Panhandles and northwestern OK. Elevated highlights have been added where the most favorable overlap of dry/windy conditions and receptive fuels exists. Deep-layer ascent overspreading a relatively deep and dry but marginally buoyant boundary layer will encourage high-based thunderstorm development during the afternoon. The storms should be fast moving and isolated enough such that appreciable rainfall accumulations will be unlikely. Isolated dry thunderstorm highlights have been introduced where lightning strikes may occur amid dry grasses. ...OH/TN Valleys into the Appalachians... Widespread breezy, occasionally dry conditions are likely to the south of the surface low, with relative humidity dropping into the 20-30 percent range by afternoon peak heating. Several areas have received appreciable rainfall accumulations within the past week. As such, the potential for wildfire-spread should remain localized. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1154 AM CDT Mon Apr 17 2023 Valid 171700Z - 181200Z The previous forecast remains valid with only minor adjustments for the latest guidance. Isolated dry thunderstorms are expected over portions of the southern High Plains along with gusty winds and low humidity. Locally elevated fire-weather conditions are also possible across the eastern US, but confidence remains too low to add an Elevated area given widespread wetting rain. Please see the previous discussion for more information. ..Lyons.. 04/17/2023 .PREV DISCUSSION... /ISSUED 0209 AM CDT Mon Apr 17 2023/ ...Synopsis... A mid-level ridge will overspread the Plains states as an upper trough pivots toward New England. A departing surface low will encourage broad, dry westerly surface winds across much of the OH/TN Valleys and points eastward. Surface lee troughing across the southern High Plains will also develop by afternoon peak heating, encouraging both dry/windy surface conditions, and isolated dry thunderstorm development. ...Southern High Plains... By afternoon peak heating, 15 mph sustained southerly surface winds overlapping 15-20 percent RH are likely across portions of northeast NM into the TX and OK Panhandles and northwestern OK. Elevated highlights have been added where the most favorable overlap of dry/windy conditions and receptive fuels exists. Deep-layer ascent overspreading a relatively deep and dry but marginally buoyant boundary layer will encourage high-based thunderstorm development during the afternoon. The storms should be fast moving and isolated enough such that appreciable rainfall accumulations will be unlikely. Isolated dry thunderstorm highlights have been introduced where lightning strikes may occur amid dry grasses. ...OH/TN Valleys into the Appalachians... Widespread breezy, occasionally dry conditions are likely to the south of the surface low, with relative humidity dropping into the 20-30 percent range by afternoon peak heating. Several areas have received appreciable rainfall accumulations within the past week. As such, the potential for wildfire-spread should remain localized. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sun Apr 16 21:28:01 UTC 2023.

MD 0546 CONCERNING HEAVY SNOW FOR PORTIONS OF WESTERN WISCONSIN AND EASTERN MINNESOTA
Mesoscale Discussion 0546 NWS Storm Prediction Center Norman OK 0354 PM CDT Sun Apr 16 2023 Areas affected...portions of western Wisconsin and eastern Minnesota Concerning...Heavy snow Valid 162054Z - 162300Z SUMMARY...Moderate to heavy snow with rates 1"+/hr ongoing. DISCUSSION...A band of moderate to heavy snow is ongoing near La Crosse, WI with reported rates up to 1.5"/hr. Temperatures are hovering around freezing regionally with stations within the heaviest portion of the snowband dropping down to freezing in the observations along and near the Mississippi River from La Crosse to Winona over the last couple of hours. RAP sounding profiles from within this region indicate deep saturation into the dendritic growth zone and mid-level lapse rates around 6.5 C/km, supporting efficient snow production and rates up to 1-1.5"/hr. Heavy snow with gusts around 25-30 mph will lead to reduced visibility to around 1/4-1/2 mi at times. ..Thornton/Grams.. 04/16/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ARX...MPX... LAT...LON 44529205 44569172 44469147 44339139 44179128 44009107 43959102 43749064 43589072 43559090 43569110 43679137 43949170 44149192 44259203 44529205 Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0243 PM CDT Sun Apr 16 2023 Valid 162000Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE GREAT LAKES REGION TO THE SOUTHEAST... ...SUMMARY... A couple of instances of strong winds and marginal hail remain possible across central and south Florida. A strong gust or two may also occur into this evening from eastern Upper Great Lakes and Lower Great Lakes, into the Southeast. ...Discussion... Prior reasoning, and outlook areas, continue to reflect current expectations. As such, aside from minor line adjustments, no changes appear necessary for this outlook issuance. ..Goss.. 04/16/2023 .PREV DISCUSSION... /ISSUED 1123 AM CDT Sun Apr 16 2023/ ...Central/south FL... Greater than weak buoyancy in the CONUS today will be confined to the peninsula south of a remnant outflow boundary in north-central FL, with the largest values of 2000-3000 J/kg MLCAPE across south FL. The larger CAPE regime should remain coincident with weaker deep-layer shear, as moderate mid-level westerlies across central FL lie within the buoyancy gradient. Scattered to widespread thunderstorm development is likely later this afternoon from the interior peninsula to the Atlantic coast sea breeze. The strongest storms will offer primary threats of isolated severe hail and damaging winds. There is low confidence regarding the evolution of a large MCS over the central Gulf. But there is potential for a remnant MCV to approach the Gulf coast of central/south FL tonight, with a lingering threat for isolated wind damage and perhaps marginal hail. ...Lower Great Lakes to the Southeast... A rather large area of lower-end damaging wind potential from strong to locally severe gusts remains evident this afternoon and evening. The relatively most favorable corridor for this to occur appears to be over the Upper OH Valley where cloud breaks were most pronounced this morning ahead of the progressive cold front. Within the warm sector ahead of the front, mid-level lapse rates will remain poor and buoyancy meager (MLCAPE less than 500 J/kg) with modest effective bulk shear as stronger deep-layer winds remain confined along/to the cool side of the front. Still, a broken band of lower-topped convection should develop within an arc along the front from Lower MI to the central Appalachians this afternoon and spread northeast across the Lower Great Lakes to the Mid-Atlantic States into this evening. Sporadic damaging winds should be expected from occasional strong gusts. Farther south in the Southeast, a remnant MCV along the AL/FL border should help focus isolated to scattered thunderstorm development near/just ahead of the trailing cold front pushing east. Some attempt at boundary-layer moisture recovery ahead of it, in the wake of yesterday's MCS that tracked across the central Gulf coast to the FL/GA border area, should support a threat for isolated strong gusts and localized damaging winds to the GA/SC coast through this evening. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 PM CDT Sun Apr 16 2023 Valid 171200Z - 181200Z ...Eastern NM, TX Panhandle, and far western OK... Hi-res model guidance has come into better agreement on the potential for isolated to widely scattered dry thunderstorms over dry fuels D2/Monday. Area model soundings show deep inverted Vs with PWATs below 1 inch over much of the Panhandle and eastern NM. Fast storm speeds and little precipitation may favor higher ignition efficiency with lighting over the dry area fuels. Isolated Dry Thunderstorm probabilities have been added to the outlook. In addition to the risk for dry T, gusty surface winds of 15-20 mph and RH below 25% will support a risk for elevated fire-weather conditions. See the previous discussion. ..Lyons.. 04/16/2023 .PREV DISCUSSION... /ISSUED 0117 AM CDT Sun Apr 16 2023/ ...Synopsis... An upper ridge will build into the Plains states as a mid-level trough impinges on the East Coast tomorrow/Monday. A surface low will meander across the Great Lakes vicinity, promoting widespread windy, occasionally dry conditions from the MS River to the Carolina Piedmont through Monday afternoon. While Elevated meteorological surface conditions are likely in spots, multiple rounds of rain east of the MS River should have tempered fuels enough to keep wildfire-spread concerns more localized. Across the southern High Plains though, dry southerly surface winds are likely by afternoon as a surface lee trough becomes established over the region due to the approach of another mid-level trough. By afternoon peak heating, 15 mph sustained south-southwesterly winds will overlap with 15-20 percent RH from the CO/NM border into far northwest OK, where fuels should be dry enough to support some wildfire-spread potential, necessitating the introduction of Elevated highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 PM CDT Sun Apr 16 2023 Valid 171200Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe weather is not expected across the continental United States Monday and Monday night. ...Discussion... A deep upper low centered over the Upper Great Lakes region early Monday is forecast to drift slowly northeastward across Lake Huron, toward the Ottawa River Valley. Broader cyclonic flow surrounding this low will continue to encompass that portion of the U.S. east of the Mississippi Valley. Meanwhile in the West, an upper low is forecast to linger off the British Columbia coast, while a short-wave trough rotating around the southern periphery of the low will move inland across the Pacific Northwest during the second half of the period. At the surface, a cold front -- trailing southward from a triple point in the vicinity of southwestern New England early -- will progress eastward across the western Atlantic, lingering only across south Florida. Meanwhile, a cold front is forecast to advance southeastward across the western states, as the aforementioned upper trough advances toward/into the Pacific Northwest region. Showers and a few thunderstorms are expected near and ahead of the front lingering over south Florida, while showers and sporadic lightning will also affect portions of the West in conjunction with the advancing storm system. Finally, isolated, high-based, diurnal convection is forecast to develop across parts of eastern New Mexico and adjacent western Texas. Daytime heating across this region will combine with modest low-level moisture returning northward on southerly flow on the back side of a Gulf of Mexico surface high, to yield weak afternoon destabilization. While a locally strong gust or two -- aided by evaporative cooling within the dry sub-cloud boundary layer -- will be possible, any severe potential appears likely to remain below the 5% threshold that would warrant any areal inclusion. Convection should dissipate through early evening. ..Goss.. 04/16/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1142 AM CDT Sun Apr 16 2023 Valid 161700Z - 171200Z ...Central Plains... Morning surface obs and visible satellite imagery show clearing skies and falling humidity are ongoing across much of central NE into north-central KS. Surface winds of 25-30 mph and higher gusts are being observed and should continue into the afternoon. The Elevated area was expanded eastward into portions of eastern NE where low-level winds will gust to 25-40 mph and RH values may fall to 20-25%. Pockets of dry fuels will likely be sufficient to support some risk for elevated to locally critical fire-weather concerns before cooler temperatures and higher RH develop this evening. See the previous discussion for additional information. ..Lyons.. 04/16/2023 .PREV DISCUSSION... /ISSUED 1256 AM CDT Sun Apr 16 2023/ ...Synopsis... A mid-level trough and associated surface low will move across the MS/OH Valley areas today, resulting in widespread deep-layer northwesterly flow overspreading the central Plains. Meanwhile, weak surface lee troughing across the southern High Plains will also support periodic bouts of dry and breezy surface conditions. Over the central Plains, guidance has trended windier and drier over much of Nebraska into Kansas and northern Oklahoma. Eastern parts of Nebraska and Kansas should experience Critical winds/RH by afternoon peak heating. However, much of this region also recently experienced appreciable rainfall accumulations, precluding the addition of fire weather highlights this outlook. Central portions of Nebraska and Kansas have received a little less rainfall recently, and newer guidance shows 15-20 mph sustained northwesterly winds overlapping 15-20 percent RH for at least a few hours during the afternoon. Since fuels should be at least modestly receptive to wildfire spread, Elevated highlights were added in a narrow corridor where dry/windy surface conditions and relatively more receptive fuels overlap. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0140 Status Updates
STATUS FOR WATCH 0140 HAS NOT BEEN ISSUED YET Read more

WW 140 SEVERE TSTM AR LA TX 152115Z - 160300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 140 NWS Storm Prediction Center Norman OK 415 PM CDT Sat Apr 15 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Arkansas Northwest Louisiana East Texas * Effective this Saturday afternoon and evening from 415 PM until 1000 PM CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 75 mph possible Scattered large hail and isolated very large hail events to 2.5 inches in diameter possible A tornado or two possible SUMMARY...Multiple thunderstorm regimes are expected into late evening with semi-discrete supercells and clusters. Large hail and damaging winds will be the main threats. The severe thunderstorm watch area is approximately along and 50 statute miles east and west of a line from 70 miles south southwest of Shreveport LA to 30 miles west of Walnut Ridge AR. 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. && OTHER WATCH INFORMATION...CONTINUE...WW 138...WW 139... 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 500. Mean storm motion vector 25035. ...Grams Read more