SPC MD 1597

MD 1597 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR CNTRL/ERN KS…NRN OK…SWRN MO


MESOSCALE DISCUSSION 1597
NWS STORM PREDICTION CENTER NORMAN OK
0258 PM CDT FRI AUG 02 2013

AREAS AFFECTED...CNTRL/ERN KS...NRN OK...SWRN MO

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 021958Z - 022200Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...ISOLATED STORMS MAY FORM AS EARLY AS 21-22Z ALONG REMNANT
OUTFLOW BOUNDARIES ACROSS PARTS OF KS. ALTHOUGH DEEP-LAYER SHEAR IS
GENERALLY MODERATE AND LARGE-SCALE FORCING FOR ASCENT IS
WEAK...AMPLE INSTABILITY WILL YIELD RISKS FOR SEVERE HAIL/WIND AND
PERHAPS A TORNADO ONCE STORMS ARE SUSTAINED. PRIMARY UNCERTAINTY IS
OVER WHEN THIS WILL OCCUR GIVEN THE SUBTLE NATURE OF LIFTING
MECHANISMS.

DISCUSSION...19Z SURFACE ANALYSIS PLACED THE MORE WELL-DEFINED OF
TWO OUTFLOW BOUNDARIES ACROSS NRN KS...WITH A DIFFUSE BOUNDARY
ACROSS NRN OK. TCU/SMALL CBS HAVE BEEN EVIDENT ALONG THE NRN
BOUNDARY WHERE CONVERGENCE APPEARS A BIT STRONGER. FARTHER SW...TCU
APPEARS TO BE INCREASING INVOF OUTFLOW/DRYLINE INTERSECTION NEAR THE
KS/OK/TX BORDER AS SURFACE TEMPERATURES HAVE BREACHED 100.
DOWNSTREAM N/S-ORIENTED CLOUD STREETS ARE EVIDENT IN MUCH OF S-CNTRL
KS INDICATIVE OF AT LEAST MODEST MLCIN IN BETWEEN THE TWO
BOUNDARIES.

CONVECTION-ALLOWING MODEL GUIDANCE VARIES MARKEDLY WITH
SPATIOTEMPORAL DETAILS OF INITIATION THIS AFTERNOON...LIKELY DUE TO
DIFFERENCES IN HANDLING OF MORNING CONVECTION AND WEAK FORCING FOR
ASCENT. BUT GIVEN THE LARGE BUOYANCY PRESENT...AT LEAST ISOLATED
CONVECTION SHOULD EVENTUALLY FORM ALONG ONE OR BOTH BOUNDARIES.
REGIONAL VWP/PROFILER DATA DO DEPICT WEAKNESSES IN THE LOW/MID-LEVEL
HODOGRAPH WHICH MAY CURTAIL SUSTAINED SUPERCELLS...BUT SUFFICIENT
EFFECTIVE SHEAR WILL EXIST FOR ORGANIZED CLUSTERS PRIMARILY CAPABLE
OF SEVERE HAIL/WIND.

..GRAMS/GOSS.. 08/02/2013

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...SGF...EAX...TSA...TOP...ICT...OUN...GID...DDC...

LAT...LON   39749888 39559765 39149516 38829427 38209363 37869360
            37299361 36629396 36159474 35799615 36029763 36509915
            36909971 37230001 37870009 38839989 39749888

via SPC Forecast Products http://www.spc.noaa.gov/products/md/md1597.html