Chance For Severe Wx Tomorrow Night…
The experts in Norman, OK working at the NWS Storm Prediction Center have included the northern and western part of our viewing area in the “slight risk” area for severe weather. This threat will arrive sometime Wednesday night into Thursday morning. Of course, we will keep a very close eye on the radar as we inch closer to the threatening time period. Our First Warning Weather Meteorologists will keep you posted on any severe weather threat that pops up. Also, keep yourself ahead of the storms by monitoring our Interactive Radar on KXAN.com. You can log on 24 hours a day, 7 days a week.
Here is the latest write up about the storms from our friends at the SPC:
SPC AC 190556 DAY 2 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1156 PM CST MON FEB 18 2013 VALID 201200Z - 211200Z ...THERE IS A SLGT RISK OF SVR TSTMS WEDNESDAY NIGHT ACROSS PARTS OF NORTHERN AND CENTRAL TEXAS... ...SYNOPSIS... A LARGE-SCALE UPPER TROUGH...CURRENTLY ADVANCING ACROSS AND EAST OF THE MISSISSIPPI VALLEY...APPEARS LIKELY TO PROGRESS OFF THE ATLANTIC COAST DURING THIS FORECAST PERIOD. IN ITS WAKE...MID-LEVEL HEIGHTS SHOULD RISE IN ADVANCE OF ANOTHER LARGE-SCALE TROUGH...WHICH IS FORECAST TO CONTINUE TO EVOLVE ACROSS THE WESTERN AND CENTRAL U.S...WITHIN THE SOUTHERN BRANCH OF A SPLIT FLOW EMERGING FROM THE PACIFIC. VARIABILITY IS SIZABLE AMONG THE MODELS AND MODEL ENSEMBLES CONCERNING SHORT WAVE IMPULSES ROUNDING THE CREST OF A BROAD AND AMPLIFIED EASTERN PACIFIC RIDGE...INTO THE TROUGH...AFTER EMANATING FROM A STRONG UPSTREAM MID-LATITUDE PACIFIC JET. BUT GUIDANCE HAS REMAINED FAIRLY CONSISTENT WITH REGARD TO A VERY STRONG INITIAL SHORT WAVE TROUGH...WHICH IS FORECAST TO EMERGE FROM THE SOUTHERN INTERMOUNTAIN REGION. THIS LATTER FEATURE STILL APPEARS LIKELY TO TAKE ON AN INCREASING NEGATIVE TILT AND BEGIN LIFTING NORTHEASTWARD AS IT CROSSES THE SOUTHERN ROCKIES INTO THE CENTRAL AND SOUTHERN PLAINS LATE WEDNESDAY NIGHT...ACCOMPANIED BY A CYCLONIC 100 KT 500 MB JET STREAK. PRIMARY SURFACE CYCLOGENESIS IS FORECAST TO TAKE PLACE ACROSS THE CENTRAL HIGH PLAINS...BUT SECONDARY WAVE DEVELOPMENT ALONG A FRONTAL ZONE ACROSS WESTERN INTO CENTRAL TEXAS IS STILL EXPECTED. MODELS INDICATE THAT THIS WILL BE ACCOMPANIED BY THE DEVELOPMENT OF A 50-70 KT SOUTHERLY 850 MB JET ACROSS THE SOUTHERN PLAINS...EVENTUALLY EXTENDING SOUTHWARD INTO THE WESTERN GULF OF MEXICO. THIS WILL AID THE INLAND ADVECTION OF MOISTURE OFF A SLOWLY MOISTENING GULF OF MEXICO BOUNDARY LAYER...AS THE ADVECTION OF MIXED LAYER AIR OFF THE HIGHER TERRAIN TO THE WEST CONTRIBUTES TO STEEPENING MID-LEVEL LAPSE RATES. THOUGH A COOL TO COLD...AND STABLE...SURFACE BASED AIR MASS MAY REMAIN ENTRENCHED ACROSS MUCH OF THE CENTRAL AND SOUTHERN PLAINS...DEEPEST TO THE NORTH OF THE TEXAS FRONTAL ZONE...DESTABILIZATION ABOVE THIS LAYER IS EXPECTED TO BECOME SUFFICIENT FOR CONSIDERABLE THUNDERSTORM ACTIVITY WEDNESDAY AND WEDNESDAY NIGHT. THE MOST SUBSTANTIVE DESTABILIZATION IS EXPECTED WITH THE BETTER RETURN FLOW OF GULF MOISTURE ACROSS PARTS OF NORTHERN AND CENTRAL TEXAS WEDNESDAY NIGHT...WHERE/WHEN SEVERE STORMS ARE POSSIBLE. ...NORTHERN AND CENTRAL TEXAS... STRONGEST MID/UPPER FORCING FOR UPWARD VERTICAL MOTION ASSOCIATED WITH THE POLAR JET WILL SHIFT ACROSS THE ROCKIES INTO THE CENTRAL PLAINS...WELL TO THE NORTH OF THE REGION. BUT UPPER FLOW WEDNESDAY NIGHT IS EXPECTED TO BECOME INCREASINGLY DIFLUENT...AND PERHAPS DIVERGENT...BETWEEN THE POLAR JET AXIS CURVING NORTHEASTWARD ACROSS THE TEXAS PANHANDLE...AND THE SUBTROPICAL JET AXIS EXTENDING EAST NORTHEAST OF THE TEXAS BIG BEND INTO THE LOWER MISSISSIPPI VALLEY. AS WARMING MID-LEVELS CAP THE MOISTURE RETURN...PRIMARY STORM INITIATION IS EXPECTED TO AWAIT THE LEADING EDGE OF STRONGER MID-LEVEL COOLING...WHICH LATEST MODEL GUIDANCE APPEARS TO BE SUGGESTING A BIT SLOWER THAN EARLIER RUNS. THIS SEEMS MOST LIKELY FROM 21/03-06Z...ALONG THE WARM FRONT JUST AHEAD OF THE SECONDARY SURFACE WAVE...NORTHEAST OF MIDLAND. CONVECTION MAY EXPAND IN COVERAGE AND INTENSIFY AS IT SPREADS EASTWARD AND ENCOUNTERS BETTER MOISTURE...AND MORE SUBSTANTIVE CAPE...IN THE PRESENCE OF STRONG DEEP LAYER SHEAR. GENERALLY ELEVATED ABOVE THE WARM FRONTAL INVERSION...LARGE HAIL MAY BE THE PRIMARY SEVERE THREAT INITIALLY. BUT THE SYNOPTIC SET-UP...STRONG LOW-LEVEL SHEAR...AND PRESENCE OF LOADED GUN TYPE SOUNDINGS ABOVE THE SURFACE BASED STABLE LAYER SUGGEST THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT SURFACE PRESSURE PERTURBATION...WITH THE RISK OF STRONG SURFACE GUSTS AS ACTIVITY SPREADS EASTWARD OVERNIGHT.
