MESO: Mesoscale Discussion 0826

ACUS11 KWNS 172056
SWOMCD
SPC MCD 172055
MTZ000-WYZ000-IDZ000-172200-

MESOSCALE DISCUSSION 0826
NWS STORM PREDICTION CENTER NORMAN OK
0355 PM CDT THU MAY 17 2007

AREAS AFFECTED...PORTIONS SRN/CENTRAL/ERN ID...SWRN-CENTRAL
MT...EXTREME NWRN WY.

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 172055Z - 172200Z

CONVECTION IS FCST TO INCREASE IN COVERAGE AND INTENSIFY ACROSS THIS
REGION THROUGH REMAINDER AFTERNOON...MOVING NEWD FROM HIGHER TERRAIN
WITH POTENTIAL FOR STG-SVR GUSTS IN LOWER ELEVATIONS OF VALLEYS AND
HIGH PLAINS. HAIL ALSO IS LIKELY WITH MOST PERSISTENT/DISCRETE
CELLS.

MODIFIED RAOBS AND RUC FCST SOUNDINGS INDICATE RAPIDLY DESTABILIZING
BOUNDARY LAYER AND WEAKENING CINH ACROSS THIS REGION...CONCURRENT
WITH INCREASE IN TCU AND SMALL CBS OVER A BROAD AREA BOUNDED ROUGHLY
BY JAC...LWT...P69...SWRN CORNER ID. FCST SOUNDINGS AND MODIFIED
RAOBS SUGGEST VERY DEEP/DRY-ADIABATIC MIXED LAYERS -- EXTENDING
ABOVE 600 MB PRESSURE LEVEL IN MANY CASES. MLCAPES ALREADY ARE NEAR
500 J/KG OVER PORTIONS BITTERROOTS AND FCST TO INCREASE TO 200-500
K/KG RANGE ACROSS MORE OF WRN MT AND SRN/ERN ID. BELT OF 30-40 KT
EFFECTIVE SHEAR EVIDENT OVER SAME AREA SUPPORTS POTENTIAL FOR SOME
TSTMS TO ORGANIZE INTO CLUSTERS OR SMALL BOWS WITH STG-SVR
DOWNDRAFTS BEING MAIN CONCERN.

SCATTERED TO WIDELY SCATTERED CONVECTION ALSO IS EVIDENT FARTHER S
ACROSS UT AND SE OVER SRN WY AND CO...BUT ANY SVR POTENTIAL S OF
OUTLINED AREA SHOULD BE VERY ISOLATED/BRIEF/PULSE IN NATURE -- GIVEN
WEAKNESS OF FLOW AND SHEAR IN CLOSE PROXIMITY TO UPPER RIDGE.

.EDWARDS.. 05/17/2007

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

ATTN...WFO...BYZ...GGW...RIW...TFX...SLC...PIH...MSO...BOI...

42551672 43291624 44981531 46271434 47081264 48020791
47680673 46910628 46190655 45600857 44590995 43611055
42291174 42071428 42151619

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
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 chris@lib.siu.edu.