ZCZC SPCSWOMCD ALL ACUS11 KWNS 200456 SPC MCD 200456 TXZ000-OKZ000-NMZ000-200700- Mesoscale Discussion 0696 NWS Storm Prediction Center Norman OK 1156 PM CDT Sun May 19 2019 Areas affected...eastern NM and portions of the OK/TX Panhandles into western TX Concerning...Severe potential...Watch likely Valid 200456Z - 200700Z Probability of Watch Issuance...80 percent SUMMARY...Thunderstorms are expected to develop by 1-3 am CDT. Large hail will be the main concern with activity through early morning. A watch will likely be needed in the next couple of hours. DISCUSSION...Strong southeasterly flow through around 1 km continues to bring rich Gulf moisture northwest across TX into eastern NM late this evening. Dewpoints have increased 8 to 16 degrees in the last 3 hours from the Davis Mountain region in western TX into southeastern NM as evidence of this strong moisture surge. Regional 00z RAOBs from CRP and DRT showed surface dewpoints of 80 and 69 F respectively. As such, deeper boundary layer moisture is expected to overspread much of western TX and into far eastern NM overnight. A resulting surge in instability will accompany the moisture return and MLCAPE values around 500 J/kg were already shifting northwest into southeast NM. As this trend continues the next few hours, modest forcing along a surface dryline and subtle impulses ejecting from eastward progressing upper trough over the western Great Basin should trigger convective initiation in the 06-08z time frame. Water vapor and IR satellite imagery indicate a subtle wave is spreading northeast across southern AZ and northern Mexico as of 0430z with increasing cloud cover and cooling cloud temps noted in addition to more agitated cloud features over southeast NM into far west TX. This initial activity will likely be elevated given the cool boundary layer. However, impressive effective shear of 60+ kt with large, curved hodographs will support rotating/supercell structures. Hail will be the main concern with this activity overnight, though a 40-50 kt south/southwesterly low level jet could result in upscale growth into a squall line or bowing segments. Given surface inhibition, the wind and tornado threat should remain limited until after sunrise. A watch will likely be needed for portions of the MCD area by around 06-07z. ..Leitman/Guyer.. 05/20/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LUB...AMA...MAF...ABQ... LAT...LON 33080403 34960410 35710420 36220395 36580355 36870265 36880202 36740147 36220095 35420082 34240128 33110180 32310249 32150294 32080338 32480392 33080403 NNNN