by Heidi Adams Cool
A concise clear how-to, the best I've found.
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Using an 'onclick' event to dynamically load a SWF
Saturday, December 5, 2009
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SPC - No MDs are in effect as of Sun May 25 09:28:05 UTC 2025No Mesoscale Discussions are in effect as of Sun May 25 09:28:05 UTC 2025. |
SPC Severe Thunderstorm Watch 321 Status ReportsWW 0321 Status Updates STATUS REPORT ON WW 321SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 NNW LBLTO 25 ENE GCK TO 45 S HLC...LEITMAN..05/25/25ATTN...WFO...TSA...DDC...ICT...SGF...OUN...STATUS REPORT FOR WS 321 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS ARC007-033-143-251040-AR . ARKANSAS COUNTIES INCLUDED AREBENTON CRAWFORD WASHINGTON KSC007-009-015-019-021-025-033-035-037-047-049-057-069-073-077-079-081-083-095-097-099-119-125-133-135-145-151-155-159-165-173-175-185-191-205-207-251040-KS . KANSAS COUNTIES INCLUDED AREBARBER BARTON BUTLER CHAUTAUQUA CHEROKEE CLARK COMANCHE COWLEY CRAWFORD EDWARDS ELK FORD GRAY GREENWOOD HARPER HARVEY HASKELL HODGEMAN KINGMAN KIOWA LABETTE MEADE MONTGOMERY NEOSHO NESS PAWNEE PRATT RENO RICE RUSHRead more |
SPC Severe Thunderstorm Watch 321WW 321 SEVERE TSTM AR KS MO OK 250445Z - 251200Z URGENT - IMMEDIATE BROADCAST REQUESTEDSevere Thunderstorm Watch Number 321NWS Storm Prediction Center Norman OK1145 PM CDT Sat May 24 2025The NWS Storm Prediction Center has issued a* Severe Thunderstorm Watch for portions of Far Northwest Arkansas Southern Kansas Far Southwest Missouri Northern Oklahoma* Effective this Saturday night and Sunday morning from 1145 PM until 700 AM CDT.* Primary threats include... Scattered large hail and isolated very large hail events to 2 inches in diameter possible Scattered damaging wind gusts to 70 mph possibleSUMMARY...Thunderstorm coverage is expected to increase tonightacross northern OK into southern KS and adjacent portions of farnorthwest AR and far southwest MO. Steep mid-level lapse rates andstrong vertical shear will support the potential for large hail.Isolated damaging gusts are also possible, particularly acrosssouthwestern KS where a potential bowing segment may move into theregion from the northwest.The severe thunderstorm watch area is approximately along and 55statute miles north and south of a line from 20 miles west southwestof Garden City KS to 30 miles east of Grove OK. For a completedepiction of the watch see the associated watch outline update(WOUS64 KWNS WOU1).PRECAUTIONARY/PREPAREDNESS ACTIONS...REMEMBER...A Severe Thunderstorm Watch means conditions arefavorable for severe thunderstorms in and close to the watch area.Persons in these areas should be on the lookout for threateningweather conditions and listen for later statements and possiblewarnings. Severe thunderstorms can and occasionally do producetornadoes.&&OTHER WATCH INFORMATION...CONTINUE...WW 319...WW 320...AVIATION...A few severe thunderstorms with hail surface and aloft to2 inches. Extreme turbulence and surface wind gusts to 60 knots. Afew cumulonimbi with maximum tops to 500. Mean storm motion vector24035....MosierRead more |
SPC May 25, 2025 Day 4-8 Severe Weather OutlookDay 4-8 Outlook Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK0353 AM CDT Sun May 25 2025Valid 281200Z - 021200Z...DISCUSSION......Wednesday/Day 4 and Thursday/Day 5...A mid-level low is forecast to move eastward into the upperMississippi Valley on Wednesday, as a cold front advancessoutheastward across the southern and eastern U.S. Thunderstormdevelopment is expected to take place along and near the frontduring the day as surface temperatures warm. An isolated severethreat will be possible Wednesday afternoon and evening, mainlyacross parts of the Southeast and southern Plains, where some areascould moderately destabilize. Mid-level flow is forecast to besomewhat weak, should could marginalize the severe threat in mostareas.On Thursday, the mid-level low is forecast to move eastward acrossthe Great Lakes, as the previously mentioned front moves slowlysoutheastward. The tail end of the front is forecast to be in thesouthern Plains, where scattered thunderstorms should developThursday afternoon. Over the southern Plains, northwest mid-levelflow is forecast to create enough deep-layer shear for isolatedsevere storms. However, predictability is too low to delineate anyareas with a potentially greater risk....Friday/Day 6 to Sunday/Day 8...From Friday to Sunday, a mid-level trough in the lower Great Lakesis forecast to move into the western Atlantic, as another troughdevelops in its wake, over the eastern U.S. Behind this trough,northwest mid-level flow will remain in place across much of thecentral and eastern U.S. In response, a relatively dry airmass isforecast remain in place across much of the central and eastern U.S.For this reason, the potential for strong thunderstorm developmentis expected to remain isolated in most areas over the weekend.Read more |
SPC Severe Thunderstorm Watch 320 Status ReportsWW 0320 Status Updates STATUS REPORT ON WW 320SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 ENE LAATO 30 SE GLD TO 50 WSW HLC...LEITMAN..05/25/25ATTN...WFO...GLD...PUB...BOU...STATUS REPORT FOR WS 320 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KSC109-203-250840-KS . KANSAS COUNTIES INCLUDED ARELOGAN WICHITA THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASEREFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIALINFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONESCLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.Read more |
SPC May 25, 2025 0730 UTC Day 3 Severe Thunderstorm OutlookSPC 0730Z Day 3 Outlook Day 3 Convective Outlook NWS Storm Prediction Center Norman OK0218 AM CDT Sun May 25 2025Valid 271200Z - 281200Z...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OFTHE SOUTHERN PLAINS EASTWARD INTO THE SOUTHEAST......SUMMARY...A marginal severe threat is expected on Tuesday from parts of thesouthern Plains eastward into the Southeast....Southern Plains...A mid-level trough will move from the southern Plains eastward intothe Ozarks on Tuesday, as flow remains primary from a westerlydirection over much of the southern Plains. At the surface, a coldfront is forecast to move southward across the Texas Hill Country,with the boundary extending eastward into the lower MississippiValley. To the south of this boundary, surface dewpoints in theupper 60s to mid 70s F will contribute to moderate instability byafternoon. The boundary will be a focus for convective initiation.Isolated to scattered thunderstorms are expected to develop in theafternoon and move east-southeastward across this moist airmass.Although deep-layer shear over much of the southern Plains isforecast to be in the 25 to 35 knot range, an isolated severe threatcould develop in areas that heat up the most. Model forecastssuggest that the MLCAPE could peak around 4000 J/kg across part ofthe Texas Hill Country by mid to late afternoon. If this were tooccur, then some of the cells could exhibit rotation near or withinthe instability maximum. An isolated threat for hail and severegusts would be possible....Southeast...A mid-level trough is forecast to move eastward into the Ozarks onTuesday, as flow ahead of the trough remains west-southwesterly. Atthe surface, a moist airmass will likely be in place across parts ofthe Southeast by afternoon. The greatest instability is forecast tothe south of a front across the central Gulf Coast, where surfacedewpoints should be in the lower to mid 70s F. Model forecastsacross the central Gulf Coast suggest that MLCAPE could peak in the2000 to 3000 J/kg range. Although deep-layer shear is forecast to berelatively weak, low-level lapse rates should become steep assurface heating takes place during the mid to late afternoon.Multicells that develop near focused corridors of low-levelconvergence could have potential for marginally severe wind gustsand hail...Broyles.. 05/25/2025Read more |
SPC May 25, 2025 0600 UTC Day 2 Convective OutlookSPC 0600Z Day 2 Outlook Day 2 Convective Outlook NWS Storm Prediction Center Norman OK1258 AM CDT Sun May 25 2025Valid 261200Z - 271200Z...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OFTHE SOUTHERN PLAINS......SUMMARY...A severe threat is expected on Monday across parts of the southernPlains, with large hail and wind damage as the primary threats.Marginally severe storms will also be possible outside the SlightRisk area from the southern Plains into the Southeast....Southern Plains/Ark-La-Tex...A shortwave mid-level trough will move eastward into the southernPlains on Monday. Ahead of the trough, a moist airmass will be inplace across much of the southern Plains. Scattered elevatedthunderstorms are expected to be ongoing across part of this airmassearly in the period, mainly across the Ark-La-Tex where warmadvection is forecast. Some of the stronger cells could pose amarginal severe threat. To the south of a cold front, warmingsurface temperatures during the day will result in strongdestabilization from the northern Texas Hill Countryeast-northeastward into northeast Texas. Thunderstorms are expectedto develop along the front during the afternoon and moveeast-southeastward into a very moist and unstable airmass.Forecast soundings near the instability axis by late afternoonacross west-central and north-central Texas have MLCAPE peakingbetween 2000 to 3000 J/kg, with 0-6 km shear between 30 and 40 knotsat most locations. 700-500 mb lapse rates are forecast to be between7.5 and 8 C/km. This environment will be favorable for supercellsand large hail, especially across west and central Texas, wherecells are more likely to remain discrete. Hailstones greater than 2inches in diameter will be possible with supercells that haveintense cores. A wind-damage threat may also accompany supercells.Further to the east, into parts of northeast and east Texas, somesolutions suggest a nearly continuous line segment will form. Inthat area, the wind-damage and hail threat would be maximized alongbowing segments, and with rotating elements within the line.Additional marginally severe storms are expected to form over partsof the southern High Plains during the late afternoon and early tomid evening....Southeast...West-southwest mid-level flow will be in place across the Southeaston Monday, with a moist and unstable airmass located throughout muchof the region. By afternoon, an east-to-west axis of moderateinstability is forecast from northern Louisiana eastward acrosssouth-central Mississippi into south-central Alabama. MLCAPE couldpeak in the 2000 to 3000 J/kg range along parts of the corridor.While large-scale ascent will be relatively weak along theinstability axis, low-level lapse rates will become steep in the midto late afternoon. Steep lapse rates and moderate instability couldbe sufficient for isolated severe gusts with semi-organizedmulticells. Hail will also be possible...Broyles.. 05/25/2025Read more |
SPC May 25, 2025 0600 UTC Day 1 Convective OutlookSPC 1200Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK1250 AM CDT Sun May 25 2025Valid 251200Z - 261200Z...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONSOF THE SOUTHERN PLAINS......SUMMARY...Severe storms, including the risk for very large hail, severe winds,and a few tornadoes, are expected across portions of the southernPlains. A risk of severe also extends across the Mid-South intonorthern Alabama....Southern Plains to northern Alabama...Subtle but potentially significant short-wave trough is expected toeject across northern Mexico into the southern High Plains latertoday. This feature will lift northeast ahead of the moresignificant trough that will advance into the southern Rockies bythe end of the period. Confluent flow across the northern Plainsfavors dominant surface high building south in the lee of theRockies. Leading edge of this air mass should spread south acrosseastern CO/western KS early in the period and a cold front shouldextend across the central TX Panhandle-northwestern OK by 18z. Theremay be a propensity for this boundary to settle a bit farther souththan the models suggest, especially if significant precipitationdevelops pre-dawn across the central Plains.Early this morning, isolated thunderstorms were gradually increasingin areal coverage across northern OK into southern KS. This activityis evolving within a warm advection zone that appears favorable forupscale growth into the early parts of the period. If an MCS maturesover eastern KS/MO it would likely turn and propagate southeast intowestern portions of the TN Valley/Mid-South later this afternoon.Damaging winds would be the primary severe threat, though some hailcould be noted.Of more concern will be the potential for organized convectionacross the southern High Plains later this afternoon. Synoptic frontshould prove instrumental in robust thunderstorm development. Latestmodel guidance suggests the strongest boundary-layer heating willoccur across far West TX/southeast NM into the TX South Plains.Forecast soundings suggest convective temperatures will easily bebreached just ahead of the cold front and thunderstorms shouldreadily develop along this wind shift, as weak large-scale ascent isexpected ahead of the approaching short wave. Additionally, 700mbtemperatures are forecast to cool a few degrees and CINH should beweaker. Steep lapse rates and seasonally high buoyancy favor strongupdrafts within a modestly sheared environment. Supercells areexpected to initiate across eastern NM/southern TX Panhandle intosouthwestern OK by 21z, then grow upscale into the evening as LLJstrengthens into this region of the southern Plains. Very large hailis possible with supercells, but a larger complex of storms mayultimately evolve. If an MCS matures, as expected, then severe windsmay become more common downstream. Some tornado risk will also benoted with supercells...Darrow/Thornton.. 05/25/2025Read more |
SPC Tornado Watch 319 Status ReportsWW 0319 Status Updates STATUS REPORT ON WW 319SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 WSW FSITO 35 WSW END...LEITMAN..05/25/25ATTN...WFO...OUN...STATUS REPORT FOR WT 319 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS OKC011-015-017-031-051-137-250640-OK . OKLAHOMA COUNTIES INCLUDED AREBLAINE CADDO CANADIAN COMANCHE GRADY STEPHENS THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASEREFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIALINFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONESCLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.Read more |
SPC Day 2 Fire Weather OutlookSPC Day 2 Fire Weather Outlook Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK1214 AM CDT Sun May 25 2025Valid 261200Z - 271200Z...NO CRITICAL AREAS......Synopsis...Fire weather concerns will remain low on D2/Monday. The upper-leveltrough will move into the Plains on Monday, with rising heights andsouthwest flow relaxing across the Southwest. A very dry air masswill remain in place, with afternoon relative humidity around 10-15percent across much of Arizona and western New Mexico. Overall, thelighter winds preclude the need for highlights on Monday...Thornton.. 05/25/2025...Please see www.spc.noaa.gov/fire for graphic product...Read more |
SPC Day 1 Fire Weather OutlookSPC Day 1 Fire Weather Outlook Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK1212 AM CDT Sun May 25 2025Valid 251200Z - 261200Z...Synopsis...A mid-level trough across the Southwest will continue to promotesouthwesterly breezes across southern Arizona into southern/centralNew Mexico this afternoon. Relative humidity reductions to around10-15 percent will overlap sustained winds around 15 mph. AnElevated area was maintained with this outlook across this regionwhere the best overlap of fuels and windy/dry conditions areexpected. Some near Critical to Critical conditions will be possiblein the lee of the higher terrain in favored downslope regions...Thornton.. 05/25/2025...Please see www.spc.noaa.gov/fire for graphic product...Read more |
