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 200740
SWOMCD
SPC MCD 200740
IAZ000-MOZ000-NEZ000-SDZ000-200945-

MESOSCALE DISCUSSION 1585
NWS STORM PREDICTION CENTER NORMAN OK
0240 AM CDT WED AUG 20 2014

AREAS AFFECTED...NORTHEAST NEB/SOUTHEAST SD AND WESTERN/SOUTHERN IA

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 200740Z - 200945Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...ISOLATED INSTANCES OF HAIL MAY BE POSSIBLE THROUGH THE
EARLY MORNING HOURS...PRIMARILY WITHIN A CORRIDOR ACROSS NORTHEAST
NEB/SOUTHEAST SD INTO WESTERN/SOUTHERN IA.

DISCUSSION...A WEAK MCV APPEARS TO BE SPREADING EAST-NORTHEASTWARD
OVERNIGHT ACROSS CENTRAL NEB...AHEAD OF A BROADER ZONE OF WEAK
HEIGHT FALLS AHEAD OF A SUBSTANTIAL SOUTHWEST STATES UPPER TROUGH.
WITH REGIONAL WSR-88D VWP DATA INDICATIVE OF A 30-40 KT LOW-LEVEL
JET...WARM ADVECTION-AIDED ISENTROPIC ASCENT FOCUSED TO THE NORTH OF
REGIONAL FRONTAL BOUNDARY WILL FURTHER AID SCATTERED ELEVATED
THUNDERSTORM DEVELOPMENT WITHIN A CORRIDOR ACROSS NORTHEAST
NEB/SOUTHEAST SD INTO WESTERN IA. WITHIN THE SOURCE REGION...STEEP
MID-LEVEL LAPSE RATES/MODERATE ELEVATED BUOYANCY EXISTS ATOP A
COOL/STABLE BOUNDARY LAYER...WITH 2000-3000+ J/KG MUCAPE LIKELY AS
PER EARLIER 00Z OBSERVED SOUNDINGS FROM NORTH PLATTE AND OMAHA. WHEN
CONSIDERING THIS ELEVATED INSTABILITY...SUFFICIENT SHEAR THROUGH THE
CLOUD-BEARING LAYER SEEMINGLY EXISTS FOR SOME UPDRAFT ROTATION. AS
SUCH...ISOLATED INSTANCES OF SEVERE HAIL WILL BE POSSIBLE THROUGH
THE EARLY MORNING HOURS...ALTHOUGH AN EVENTUAL TREND FOR UPDRAFT
MERGERS/CLUSTERING WILL TEND TO MITIGATE THE POTENTIAL FOR LARGER
HAIL STONES OVER TIME.

..GUYER/CARBIN.. 08/20/2014

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

ATTN...WFO...DMX...EAX...FSD...OAX...GID...LBF...

LAT...LON   43769874 43079646 42149439 40579353 41089601 41449815
            42519844 43769874



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