ACUS11 KWNS 272051 SWOMCD SPC MCD 272050 IDZ000-ORZ000-WAZ000-NVZ000-CAZ000-272215- Mesoscale Discussion 0878 NWS Storm Prediction Center Norman OK 0350 PM CDT Wed May 27 2026 Areas affected...portions of the Pacific Northwest and northern Great Basin Concerning...Severe potential...Watch unlikely Valid 272050Z - 272215Z Probability of Watch Issuance...5 percent SUMMARY...Scattered storms on the northern periphery of a deep upper low may pose a risk for severe wind gusts or hail. DISCUSSION...As of 2045 UTC, regional radar imagery showed scattered thunderstorms intensifying over portions of northern NV, eastern OR and southwestern ID. Aided by ascent from an embedded shortwave trough on the northern periphery of a deep upper low over the West Coast, additional storm development/intensification is likely this afternoon and evening. Filtered diurnal heating, relatively moist surface conditions for May (dewpoints near 50 F) and cold temperatures aloft are helping to support moderate destabilization with 500-1000 J/kg of MLCAPE present. An increase in lightning and cooling cloud tops over the last few hours suggests convection is maturing, with several stronger updrafts noted. 50+ kt of east/southeasterly flow aloft is evident on area VADs and RAP soundings. Veering wind profiles with northwesterly storm motions will be sufficient for occasional storm organization into multi cell clusters or occasional supercells. The steep low and mid-level lapse rates will support a risk for severe/damaging gusts given the potential for strong downdrafts. However, some hail is also possible, especially with any rotating storms. The primary limiting factor remains the more limited instability. Cloud cover has lingered farther west, curtailing diurnal destabilization. While cold mid-level temperatures will allow for some destabilization beneath the northern parts of the upper low, persistent storm organization may be confined to areas of better buoyancy. Thus, some severe wind and hail risk is evident over parts of northern NV, southeast OR, and southwestern ID through this evening. However, confidence in a widespread sustained severe risk is low and a WW is unlikely. ..Lyons/Gleason.. 05/27/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PIH...MSO...BOI...LKN...OTX...PDT...REV...MFR... STO...PQR... LAT...LON 42892292 44412143 45481898 46131677 45731516 44211413 42801567 41421903 41122099 41242183 41392231 42892292 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN