Severe Storm Outlook Narrative (AC)
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
ACUS11 KWNS 260355
SWOMCD
SPC MCD 260354
IAZ000-MNZ000-NEZ000-SDZ000-260600-

MESOSCALE DISCUSSION 1539
NWS STORM PREDICTION CENTER NORMAN OK
1054 PM CDT SAT JUL 25 2015

AREAS AFFECTED...PORTIONS OF SERN SD...SRN MN...NWRN IA...NERN NEB

CONCERNING...SEVERE THUNDERSTORM WATCH 453...

VALID 260354Z - 260600Z

THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 453
CONTINUES.

SUMMARY...AN MCS SPREADING ESEWD/SEWD ACROSS SERN SD INTO SWRN MN
CONTINUES TO POSE A RISK FOR ISOLATED DMGG WIND GUSTS IN WW 453.
WHILE STORMS WILL SPREAD ESEWD/SEWD OUT OF WW 453 DURING THE
OVERNIGHT HOURS...ADDITIONAL/DOWNSTREAM WW ISSUANCE IS NOT
ANTICIPATED.

DISCUSSION...A LEADING-LINE/TRAILING-STRATIFORM MCS CONTINUES
TRACKING ESEWD/SEWD ACROSS SERN SD INTO SWRN MN WITH A HISTORY OF
OCCASIONAL 40-50-KT OBSERVED SFC WIND GUSTS. MODERATE MID-LEVEL
LAPSE RATES PRECEDING THE CONVECTIVE LINE SURMOUNTING RICH PBL
MOISTURE WILL CONTINUE FOSTERING ADEQUATE POTENTIAL BUOYANCY FOR
STRONG CONVECTION TO TRACK ESEWD/SEWD INTO THE OVERNIGHT HOURS AS IT
INTERACTS WITH 30-45 KT OF EFFECTIVE BULK SHEAR. THIS ACTIVITY WILL
LIKELY CONTINUE PROGRESSING BEYOND THE SRN/ERN EXTENT OF WW 453
DURING THE OVERNIGHT HOURS...AND ISOLATED DMGG WIND GUSTS CANNOT BE
RULED OUT. HOWEVER...THE OVERALL SVR RISK/CONVECTIVE ORGANIZATION
SHOULD DIMINISH AS /1/ MLCINH FOR INFLOW INTO THE MCS GROWS WITH
NOCTURNAL COOLING.../2/ LARGE-SCALE ASCENT REMAINS WEAK...AND
/3/ INFLOW-REGION VWP DATA IMPLY ONLY 10-20 KT OF LOW-LEVEL FLOW
YIELDING ONLY MODEST SYSTEM INFLOW. CONVECTIVE PROCESSING OF THE
BUOYANCY WILL LEAD TO NIL SVR POTENTIAL IN THE WAKE OF THE MCS.

..COHEN.. 07/26/2015

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

ATTN...WFO...MPX...DMX...FSD...OAX...

LAT...LON   43349881 44029626 44049487 43549409 43119393 42729425
            42399576 42679796 43349881



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.