SWOMCD
SPC MCD 072055
IAZ000-NEZ000-SDZ000-072230-
MESOSCALE DISCUSSION 1812
NWS STORM PREDICTION CENTER NORMAN OK
0355 PM CDT FRI AUG 07 2009
AREAS AFFECTED...ERN NEB AND ADJACENT PORTIONS OF SERN SD...WRN IA
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 072055Z - 072230Z
TRENDS ARE BEING CLOSELY MONITORED FOR THE POSSIBILITY OF A RAPIDLY
INCREASING SEVERE THREAT WHICH LIKELY WILL REQUIRE A WW.
LATEST RUC GUIDANCE IS SUGGESTIVE THAT MID-LEVEL FORCING FOR
ASCENT...ASSOCIATED WITH A WEAK LOW AMPLITUDE IMPULSE LIFTING
THROUGH THE CENTRAL PLAINS...HAS CONTRIBUTED TO WEAK LOWER/MID
TROPOSPHERIC COOLING OVER PARTS OF CENTRAL/EASTERN NEBRASKA.
CONSIDERABLE INHIBITION REMAINS...BUT THIS COULD BEGIN TO CHANGE BY
22-00Z...WITH LOW-LEVEL WARMING AND LIFT ALONG/NORTH OF A 30-40 KT
SOUTHWESTERLY 850 MB JET DEVELOPING NORTHEASTWARD INTO THE MID
MISSOURI VALLEY. A VERY WARM AND MOIST BOUNDARY LAYER ACROSS THIS
REGION IS ALREADY CHARACTERIZED BY MODERATE TO STRONG POTENTIAL
INSTABILITY...AND FURTHER DESTABILIZATION/WEAKENING OF INHIBITION
COULD YIELD RAPID INTENSE STORM DEVELOPMENT.
IF THIS OCCURS...STRONG SHEAR IN THE LOWEST 4-5 KM AGL...AND LARGE
CLOCKWISE CURVED LOW-LEVEL HODOGRAPHS...WILL BE FAVORABLE FOR
SUPERCELLS CAPABLE OF PRODUCING LARGE HAIL/ISOLATED TORNADOES.
HOWEVER...VERY WARM LOW-LEVEL THERMODYNAMIC PROFILES CHARACTERIZED
BY LARGE TEMPERATURE/DEW POINT SPREADS ARE EXPECTED TO MORE
PROMINENTLY SUPPORT STRONG DOWNBURSTS AND RELATIVELY COLD OUTFLOWS
THAT COULD CONGEAL INTO A FORWARD PROPAGATING MESOSCALE CONVECTIVE
SYSTEM ACROSS THE MID MISSOURI VALLEY BY EARLY EVENING. RELATIVELY
WEAK HIGH LEVEL FLOW MAY ENHANCE THIS POTENTIAL...BY ALLOWING A
FAVORABLE SYSTEM RELATIVE FLOW CONFIGURATION TO DEVELOP WHICH WILL
SPREAD ANVIL CLOUD COVER/PRECIPITATION TO THE REAR OF ANY
CONSOLIDATING GUST FRONT.
..KERR.. 08/07/2009
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...DMX...FSD...OAX...GID...LBF...
LAT...LON 40879926 41679907 42429844 43039782 43389675 42919571
42119503 41149549 40549635 40149755 40229848 40879926
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.
No comments:
Post a Comment