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DAY 2 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0100 AM CDT WED APR 20 2011 VALID 211200Z - 221200Z ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE SOUTH-CENTRAL PLAINS TO OZARKS/LOWER MO VALLEY... ...SOUTHERN PLAINS TO LOWER MO VALLEY/OZARKS/MIDDLE MS VALLEY... AN UPPER TROUGH WILL SPREAD EASTWARD FROM THE ROCKIES TO THE NORTH-CENTRAL PLAINS THURSDAY/THURSDAY NIGHT. AS THIS OCCURS...SURFACE CYCLOGENESIS IS ANTICIPATED ACROSS THE SOUTH-CENTRAL HIGH PLAINS ON THURSDAY...WITH UPPER 50S F TO MIDDLE 60S F SURFACE DEWPOINTS RETURNING NORTH-NORTHWESTWARD TO THE EAST OF A MODESTLY SHARPENING SOUTHERN HIGH PLAINS DRYLINE. HAVE INTRODUCED A SLIGHT RISK FOR WHAT COULD BE A MULTI-ROUND OF SEVERE HAIL /LIKELY THE PRIMARY HAZARD FOR THE PERIOD/...WITH THE GREATEST CERTAINTY/COVERAGE ANTICIPATED THURSDAY NIGHT ACROSS THE REGION. INITIALLY...ELEVATED TSTMS...SOME CAPABLE OF SEVERE HAIL...ARE LIKELY TO BE ONGOING THURSDAY MORNING ACROSS THE SOUTHERN PLAINS AND ADJACENT ARKLATEX/OZARKS. A PERSISTENT WARM ADVECTION REGIME MAY MAINTAIN SOME STRONG/SEVERE TSTMS...AT LEAST ON AN ISOLATED BASIS...DURING THE DAY TO THE NORTH OF THE NORTHWARD RETURNING SURFACE FRONTAL ZONE/ATTENDANT MOIST SECTOR. FARTHER SOUTHWEST...ACROSS WESTERN OK AND MUCH OF WESTERN TX...A RELATIVELY STRONG CAP COUPLED WITH ANTICIPATED MODEST LARGE SCALE FORCING COINCIDENT WITH THE NORTH-SOUTH ORIENTED DRYLINE PROVIDES UNCERTAINTY REGARDING THE LIKELIHOOD/COVERAGE OF ANY SURFACE BASED TSTMS THURSDAY AFTERNOON/EARLY EVENING. NUMERICAL GUIDANCE VARIABILITY ALSO STILL EXISTS AT THIS JUNCTURE REGARDING THE DRYLINE POSITION AND THE SPATIAL EXTENT OF THE NORTHWARD RETURNING MOIST SECTOR. BUT PROVIDED ISOLATED SURFACE BASED DEEP CONVECTIVE DEVELOPMENT...SOME SUPERCELLS CAPABLE OF MAINLY LARGE HAIL WOULD BE POSSIBLE THURSDAY AFTERNOON/EVENING. BY THURSDAY NIGHT...AS SLIGHT HEIGHT FALLS GRAZE THE REGION AND A 50+ KT LOW LEVEL JET NOCTURNALLY DEVELOPS...THE MOST LIKELY/HIGHEST CONFIDENCE SCENARIO IS FOR TSTMS TO INCREASE AFTER DARK WITHIN A CORRIDOR ACROSS THE SOUTH-CENTRAL PLAINS EAST-NORTHEASTWARD TO THE LOWER MO VALLEY/OZARKS AND MIDDLE MS VALLEY. GIVEN MODERATE ELEVATED INSTABILITY/STEEP MID LEVEL LAPSE RATES COUPLED WITH AMPLE SHEAR THROUGH THE CLOUD BEARING LAYER...ELEVATED SUPERCELLS WILL BE POSSIBLE WITH BOUTS OF SEVERE HAIL. ...INTERIOR GULF COAST/SOUTHEAST STATES... TSTMS WILL REMAIN POSSIBLE INTO THURSDAY ALONG THE STALLING WEST-EAST FRONTAL ZONE ACROSS THE REGION. ESPECIALLY GIVEN THE POTENTIAL FOR LINGERING CLOUD COVER/CONVECTION INTO THURSDAY...THE DEGREE OF DESTABILIZATION ALONG/SOUTH OF THE FRONT IS UNCERTAIN DURING THE AFTERNOON. WHILE SOME STRONG STORMS CAPABLE OF PULSE-TYPE WIND/HAIL MAY BE POSSIBLE...AFOREMENTIONED UNCERTAIN DESTABILIZATION...COMBINED WITH NEBULOUS LARGE SCALE FORCING/WEAKENING LOW LEVEL CONVERGENCE...PRECLUDES SEVERE PROBABILITIES AT THIS TIME. ...CENTRAL ROCKIES TO CENTRAL HIGH PLAINS... TIED TO THE ADVANCING SHORTWAVE TROUGH...LARGE SCALE FORCING FOR ASCENT WILL OVERSPREAD THE CENTRAL ROCKIES WITH TSTMS INCREASING THURSDAY AFTERNOON. IT IS POSSIBLE THAT A FEW STORMS MAY BE CAPABLE OF GUSTY WINDS AND/OR MARGINALLY SEVERE HAIL FROM UT INTO NORTHERN CO/SOUTHERN WY THURSDAY AFTERNOON/EARLY EVENING...BUT MODEST PW/POTENTIAL INSTABILITY WILL KEEP ANY SEVERE THREAT REMOTE. ..GUYER.. 04/20/2011
I guess I'll say it....does this "threat" even warrant a thread? Anywho, here's my take. I've seen piles of doggie doo that have more potential for us than this system. One, there's a ENE surface wind component. Two, dew points are in the 40Fs. Three, there's a 1020+mb HP sitting over the Great Lakes. Four, lifted indices are WAY positive. Five, there's hardly any energy coming through the 500mb level. Six, there's almost a ridge-like amplitude at the H5 level. Seven, the upper level jet structure is way north of here, so we get no upper level help. Eight, it looks like we're going to be socked in with a cloud deck given the saturation levels at H7. The only thing this "event" has going for it is little to no convective inhibition, but without all the other party goers, it means very little.
glad I'm not the only one seeing this as a bust-
Its a ways off, but next Monday and Tuesdays threat probably deserves a thread more so than tomorrow and Sat.
I wish whoever is praying for these storms and rain would stop so I can get a garden in the ground.