MESO: Mesoscale Discussion 2057

ACUS11 KWNS 050051
SWOMCD
SPC MCD 050051
IAZ000-NEZ000-SDZ000-KSZ000-050145-

MESOSCALE DISCUSSION 2057
NWS STORM PREDICTION CENTER NORMAN OK
0751 PM CDT THU OCT 04 2007

AREAS AFFECTED...NORTH CENTRAL KS/PARTS OF CENTRAL AND ERN NEB/WRN
IA

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 050051Z - 050145Z

TSTMS WILL INCREASE IN AREAL COVERAGE THIS EVENING FROM NORTH
CENTRAL KS NEWD THROUGH ERN NEB...WITH NEW DEVELOPMENT EXPECTED
LATER THIS EVENING INTO WRN IA AND TOWARD THE FSD AREA. ISOLATED
STRONGER STORMS WILL REMAIN POSSIBLE...WITH A FEW POTENTIALLY
BECOMING SEVERE. WW IS NOT APPARENT AT THIS TIME...BUT CONVECTIVE
TRENDS WILL BE MONITORED FOR ANY SIGNS OF GREATER INTENSIFICATION.

REGIONAL RADARS HAVE SHOWN TSTMS INCREASING IN BOTH COVERAGE AND
INTENSITY SINCE 23Z ACROSS NORTH CENTRAL KS INTO ADJACENT PARTS OF
SRN NEB...PRIOR TO THE LOSS OF DAYTIME HEATING. THIS ACTIVITY
DEVELOPED IN THE VICINITY OF THE DIFFERENTIAL HEATING BOUNDARY WHICH
EXTENDED FROM THE SURFACE LOW LOCATED TO THE S OF HLC AND THEN NEWD
INTO SOUTH CENTRAL TO EAST CENTRAL NEB. ALTHOUGH TSTMS HAVE TENDED
TO WEAKEN ONCE THEY TRACK N OF THIS BOUNDARY...TSTMS ALONG AND S OF
THIS BOUNDARY ARE BEING SUPPORTED BY MODERATE INSTABILITY AND
EFFECTIVE SHEAR OF 30-40 KT. 00Z OMA SOUNDING INDICATED A MID LEVEL
INVERSION WHICH APPEARS TO BE LIMITING THE COVERAGE THUS FAR FOR
MORE STRONG TO SEVERE TSTMS. THE LOSS OF DAYTIME HEATING SUGGESTS
THAT SURFACE BASED TSTMS SHOULD BECOME LESS LIKELY.

A STRENGTHENING SLY LLJ IN THE CENTRAL PLAINS WILL MAINTAIN LOW
LEVEL DESTABILIZATION THROUGH MOISTURE/WARM AIR ADVECTIONS INTO THE
MID MO VALLEY. THIS COMBINED WITH SOME ASCENT ATTENDANT TO NEWD
MOVING MID LEVEL IMPULSE NOW LOCATED OVER NRN KS/SRN NEB WILL
SUPPORT ADDITIONAL TSTM DEVELOPMENT THIS EVENING.

.PETERS.. 10/05/2007

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

ATTN...WFO...DMX...FSD...OAX...TOP...GID...

39469820 39389915 40019941 40989883 41909814 42739701
42879564 42259453 40909557 40089697

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@PO.UIUC.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.