SPC 1730Z Day 2 Outlook
DAY 2 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1159 AM CDT SAT MAY 25 2013 VALID 261200Z - 271200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE NORTHERN AND CENTRAL PLAINS... ...PLAINS... WEAK HEIGHT FALLS ARE EXPECTED TO SPREAD INTO THE NRN HIGH PLAINS LATE IN THE PERIOD AS A WEAK SHORT-WAVE TROUGH EJECTS ACROSS THE NRN ROCKIES TO A POSITION FROM WRN MT INTO NWRN WY AT 27/12Z. THIS FEATURE WILL UNDOUBTEDLY ENHANCE THE WWD MOVEMENT OF BOUNDARY LAYER MOISTURE ACROSS THE NRN HIGH PLAINS TOWARD SCNTRL MT AS ELY LOW LEVEL COMPONENT...AT LEAST 1KM DEEP...FORCES LOWER 50S SFC DEW POINTS TOWARD BIL. WHILE LARGE SCALE ASCENT WITH SHORT-WAVE WILL LAG PEAK HEATING...IT APPEARS CONVECTION SHOULD EVOLVE OFF THE NRN ABSAROKA RANGE...AND NRN BIG HORN MOUNTAINS. THIS ACTIVITY SHOULD THEN EVOLVE AND SPREAD TOWARD SERN MT/EXTREME NERN WY WHERE SHEAR PROFILES WILL FAVOR SUPERCELLS. LARGE HAIL AND ISOLATED TORNADOES CAN BE EXPECTED WITH THIS ACTIVITY. IF SUFFICIENT INSTABILITY DEVELOPS ACROSS THIS REGION THERE IS CONCERN FOR VERY LARGE HAIL AND POSSIBLY A STRONG TORNADO. 23Z FORECAST SOUNDING AT 4BQ SUPPORTS THIS POSSIBILITY AS IT DEPICTS A VERY FAVORABLE PROFILE FOR STRONG ROTATING UPDRAFTS WITH SBCAPE IN EXCESS OF 2500 J/KG. FARTHER SOUTH ACROSS THE CNTRL PLAINS...IT/S NOT PARTICULARLY CLEAR IF A DISTURBANCE WILL EJECT ACROSS CO DURING THE AFTERNOON HOURS BUT FORECAST HEIGHT FIELDS ARE SUPPRESSED SOMEWHAT ACROSS THIS REGION INTO THE EVENING HOURS SUGGESTING THE POSSIBILITY. ADDITIONALLY...LLJ IS EXPECTED TO INCREASE MARKEDLY ACROSS KS BY 27/00Z WHICH SUGGESTS A WEAK FEATURE MAY BE FLATTENING THE RIDGE ACROSS THIS REGION. WITH BACKING FLOW EXPECTED ACROSS NEB IT APPEARS E-W SFC BOUNDARY SHOULD ESTABLISH ITSELF JUST NORTH OF I-70 AND THIS WILL PROVE FAVORABLE FOR ROBUST CONVECTIVE DEVELOPMENT DURING THE LATE AFTERNOON/EVENING HOURS...ESPECIALLY AS LLJ IMPINGES ON THE BOUNDARY. STRONG HEATING ACROSS WRN KS WILL LIKELY CONTRIBUTE TO INITIAL TSTM DEVELOPMENT AND DEEP LAYER SHEAR SEEMS ADEQUATE FOR MAINTENANCE OF SLOW MOVING SUPERCELLS AND STRONG/ORGANIZED MULTI-CELL CLUSTERS. ROUGHLY 20KT OF 500MB FLOW WILL ALSO EXTEND SWD ALONG THE DRYLINE ACROSS WEST TX. IT APPEARS DIURNAL HEATING WILL BREAK THE CAP ACROSS THIS REGION WHERE SBCAPE SHOULD BE AOA 3000 J/KG. AT THIS TIME WILL MAINTAIN 5 PERCENT SEVERE PROBS FOR HAIL/WIND ALONG THE SRN DRYLINE BUT THERE IS CONCERN PROBABILITIES MAY NEED TO BE INCREASED TO ACCOUNT FOR SCT ORGANIZED MULTI-CELL CLUSTERS. ..DARROW.. 05/25/2013
via SPC Forecast Products http://www.spc.noaa.gov/products/outlook/day2otlk_1730.html
Be First to Comment