STORM PREDICTION CENTER...NWS/NCEP...NORMAN OK
DAY 2 CONVECTIVE OUTLOOK...REF AWIPS GRAPHIC PGWI47 KWNS.
VALID 171200Z - 181200Z
THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM
40 NNE LAR 20 SW DGW 50 NE DGW 25 WSW RAP 55 SSE Y22 20 N MBG
45 ENE MBG 30 SW ABR 15 NNW 9V9 30 NNE MHN 40 SW MHN 25 NE SNY
25 ENE CYS 40 NNE LAR.
THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM
15 NW ELD 10 NW DYR 30 NW HOP 45 NNE BWG 40 WNW LOZ 20 WSW LOZ
30 WNW TYS 55 SSW TYS 35 N AHN 30 ESE AND CAE 35 ESE AGS
65 ESE MCN 15 SSE CSG 30 SSW SEM 40 SE LUL 25 W MSY 40 WSW 7R4
30 S BPT 25 NNE HOU 15 W LFK 25 SW SHV 15 NW ELD.
GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 40 NNW SHR 35 W DIK
45 NE DVL 10 ESE TVF 15 SSW AXN 20 SW ANW 35 NE AKO 20 SSE LIC
30 SW COS ASE 25 NW GJT 30 WNW 4HV 50 SW DPG 55 NNE ENV 20 SSW JAC
40 NNW SHR.
GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 20 E CRP 40 NW ALI
20 S SAT 35 E TPL 15 SW PRX 10 NW UMN 40 NNW STL 20 SW MIE
25 N PSK 20 WSW HKY 10 SSW ILM.
...SYNOPSIS...
UPPER LOW MOVING ACROSS THE SRN PLAINS TODAY WILL MOVE SLOWLY EWD
INTO THE LOWER MS VLY AND GRADUALLY WEAKEN SATURDAY AND SATURDAY
NIGHT. UPSTREAM...A COLD UPPER TROUGH WILL SETTLE SWD INTO THE
NWRN STATES WITH SEVERAL EMBEDDED SHORTWAVE TROUGHS EJECTING NEWD
FROM THE PAC NW INTO THE NRN HIGH PLAINS. AT THE SURFACE...A WEAK
LOW WILL LIKELY REMAIN INVOF CNTRL AR WITH A WARM FRONT MOVING NWD
INTO THE TN VLY. A WEDGE OF COOLER AIR WILL SLIDE SWD INTO THE SRN
APPALACHIANS. MEANWHILE...UPSTREAM...SEVERAL SURGES OF COOLER AIR
WILL FOLLOW EACH SUCCESSIVE MIDLEVEL DISTURBANCE THAT PASSES NEWD
ACROSS THE NRN HIGH PLAINS THROUGH THE PERIOD.
...LWR MS VLY NEWD INTO THE SERN STATES...
SEVERE FOCUS BECOMES SOMEWHAT MORE DIFFUSE WITH TIME ON SATURDAY
THAN OBSERVED IN PREVIOUS DAYS GIVEN THAT THE UPPER SYSTEM BEGINS
TO WEAKEN. THE ANTICIPATED WEAKENING TREND WILL PROBABLY BE AT A
SLOWER PACE THAN REPRESENTED BY SHORT TERM MODELS. MORNING FOCUS
FOR POSSIBLE LARGE HAIL OR DAMAGING WIND GUSTS WILL CONTINUE FROM
THE FRIDAY NIGHT ACTIVITY AS IT MOVES ENEWD INTO PARTS OF WRN
TN/NRN MS/SRN KY ON NOSE OF 40-45 KT SSWLY LOW LEVEL JET. THIS
ACTIVITY SHOULD WEAKEN DURING THE MORNING AS IT MOVES BEYOND THE
STRONGEST MASS CONVERGENCE.
DURING SATURDAY AFTERNOON...POTENTIAL WILL EXIST FOR TSTMS TO
DEVELOP ALONG OUTFLOW BOUNDARIES/COLD FRONT NEAR THE MS RVR FROM
ERN AR/W TN SWD INTO PARTS OF NRN LA AND EWD INTO THE TN VLY.
STRONGEST MIDLEVEL FLOW SHOULD EXIST ACROSS THE MS DELTA NEWD INTO
NRN AL/TN AND COULD SUPPORT SUPERCELLS GIVEN MLCAPE VALUES OF 1500-
2500 J/KG. LARGE HAIL AND DAMAGING WINDS WILL BE THE PREDOMINATE
SEVERE THREATS. FARTHER S AND SW...INCREASING MIDLEVEL CAP AND
WEAKER DEEP LAYER SHEAR SHOULD LIMIT THE SEVERE THREATS INTO ERN TX
AND TOWARD THE CNTRL/ERN GULF COASTAL AREAS.
ANOTHER MAXIMUM IN SEVERE POTENTIAL MAY EXIST ALONG SRN PERIPHERY
OF THE WEDGE FRONT ACROSS NRN GA INTO PARTS OF SC. WARM SECTOR
SHOULD DESTABILIZE WITH MLCAPES OF 1500-2000 J/KG. DEEP LAYER
SHEAR WILL INITIALLY BE WEAK...BUT SHOULD INCREASE AS UPPER JET
STREAK APPROACHES THE REGION DURING THE EVENING. THE ONLY NEGATIVE
SEEMS TO BE THAT MOST OF THE MASS CONVERGENCE WILL BE POINTED MORE
INTO THE TN VLY THAN POINTS TO THE EAST.
...NRN HIGH PLAINS...
UPPER DIFFLUENCE SHOULD INCREASE OVER THE NRN HIGH PLAINS SATURDAY
EVENING BENEATH COUPLED JET STREAKS. LOW LEVEL FLOW WILL RESPOND
WITH A MODEST SLY LOW LEVEL JET DEVELOPING...AIDING IN LOW-MIDLEVEL
FRONTOGENESIS. HEATING ON THE HIGHER TERRAIN SHOULD AID IN HIGH
BASED TSTMS ACROSS THE WY MOUNTAINS AND BLACK HILLS SATURDAY
AFTERNOON...WHICH SHOULD MOVE ONTO THE HIGH PLAINS DURING THE
EVENING. DEEP LAYER SHEAR WILL BE SUPPORTIVE FOR SUPERCELLS...AND
IF A FEW TSTMS CAN ROOT INTO THE INCREASINGLY MOIST BOUNDARY
LAYER...POTENTIAL WILL EXIST FOR LARGE HAIL AND DAMAGING WINDS.
ACTIVITY IS LIKELY TO DEVELOP/MOVE NEWD ALONG THE COLD FRONT INTO
SD AND PERHAPS ND DURING THE OVERNIGHT HOURS IN ONE OR MORE
CLUSTERS.
..RACY.. 05/16/03
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED FOR 0800Z
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