Alert archive / Missouri / Mesoscale Discussions in 2012
Mesoscale Discussion 2064
The Storm Prediction Center issued this mesoscale discussion at Oct 17, 2012, 12:55 PM CDT for 5 counties in Arkansas; 35 counties in Missouri. It was in force for 95 min.
The area
The outline as issued.
The facts
- Issued
- Oct 17, 2012, 12:55 PM CDT (17:55 UTC)
- Expired
- Oct 17, 2012, 2:30 PM CDT
- In force
- 95 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 40 counties
Baxter County, AR, Benton County, AR, Boone County, AR, Carroll County, AR, Marion County, AR, Barry County, MO, Camden County, MO, Cedar County, MO, Christian County, MO, Cole County, MO, Crawford County, MO, Dade County, MO, Dallas County, MO, Dent County, MO, Douglas County, MO, Gasconade County, MO, Greene County, MO, Hickory County, MO, Howell County, MO, Iron County, MO, Jasper County, MO, Laclede County, MO, Lawrence County, MO, Maries County, MO, McDonald County, MO, Miller County, MO, Newton County, MO, Osage County, MO, Ozark County, MO, Phelps County, MO, Polk County, MO, Pulaski County, MO, Reynolds County, MO, Shannon County, MO, Stone County, MO, Taney County, MO, Texas County, MO, Washington County, MO, Webster County, MO, Wright County, MO
The radar
The Springfield radar (KSGF), 91 km from the middle of the area, began a volume at 17:58 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Springfield, MO (KSGF), launched 12:00Z, 5.9 hours before the alert went out and 138 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 1 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 745 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- 205 m²/s²
- 0-3 km storm-relative helicity
- 248 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
460
ACUS11 KWNS 171755
SWOMCD
SPC MCD 171755
MOZ000-ARZ000-171930-
MESOSCALE DISCUSSION 2064
NWS STORM PREDICTION CENTER NORMAN OK
1255 PM CDT WED OCT 17 2012
AREAS AFFECTED...NRN AR...SRN/CNTRL MO
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE
VALID 171755Z - 171930Z
PROBABILITY OF WATCH ISSUANCE...40 PERCENT
SUMMARY...A LINE OF THUNDERSTORMS IS FORECAST TO DEVELOP FROM CNTRL
MO SWWD INTO NRN AR THIS AFTERNOON. AREA IS BEING MONITORED FOR
INCREASING THREAT OF DAMAGING WINDS/MARGINALLY SVR HAIL AND AN
ISOLATED TORNADO. WW IS POSSIBLE.
DISCUSSION...MESOANALYSIS AT 17Z SHOWS AN AREA OF SURFACE LOW
PRESSURE OVER ERN OK...WITH A COLD FRONT EXTENDING NEWD INTO NRN MO.
VISIBLE SATELLITE IMAGERY SHOWS THAT SOME CLEARING OF LOW-LEVEL
STRATUS IS OCCURRING AHEAD OF THE FRONT FROM NWRN AR INTO S-CNTRL
MO...WHICH IS AIDING IN TEMPERATURES WARMING INTO THE MID 60S. IN
ADDITION...SURFACE DEWPOINTS ARE SLOWLY RISING INTO THE UPPER 50S TO
LOW 60S. THIS SURFACE AIRMASS COMBINED WITH STEEP MIDLEVEL LAPSE
RATES WILL YIELD AFTERNOON MLCAPE VALUES FROM 1000 J/KG OVER NRN AR
TO AROUND 500 J/KG IN CNTRL MO. SATELLITE IMAGERY INDICATES A BAND
OF FORCED ASCENT IS SPREADING EWD ACROSS ERN KS...AND IS LIKELY
SUPPORTING THE RECENT INITIATION OF THUNDERSTORMS ALONG THE COLD
FRONT. THESE STORMS ARE FORECAST TO ACCELERATE EWD ACROSS NRN AR AND
SRN/CNTRL MO DURING THE AFTERNOON. GIVEN THE MARGINAL BUOYANCY...IT
IS UNCERTAIN WHETHER STORMS WILL INTENSIFY TO SVR LEVELS.
HOWEVER...STRONG FORCING FOR ASCENT AND VERTICAL WIND SHEAR PROFILES
MAY COMPENSATE...AND SUPPORT A THREAT FOR DAMAGING WIND
GUSTS...MARGINALLY SVR HAIL...AND PERHAPS AN ISOLATED TORNADO.
..GARNER/THOMPSON.. 10/17/2012
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PAH...LSX...LZK...SGF...TSA...
LAT...LON 38269059 37319059 36089253 36039427 37169461 37959399
38719211 38269059SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 17, 3:44 PM CDT | Mesoscale Discussion | SPC | Arkansas, Ashley, Bradley, Calhoun, Chicot, Clay and 29 more | 61 min |
| Oct 17, 5:21 PM CDT | Tornado Watch | SPC | Arkansas, Baxter, Boone, Bradley, Calhoun, Carroll and 57 more | 7 hr |
| Oct 17, 6:29 PM CDT | Mesoscale Discussion | SPC | Ashley, Bradley, Calhoun, Chicot, Columbia, Drew and 5 more | 91 min |
| Oct 17, 11:45 AM CDT | Mesoscale Discussion | SPC | Audrain, Lewis, Lincoln, Marion, Monroe, Montgomery and 7 more | 90 min |
| Oct 17, 1:58 PM CDT | Severe Thunderstorm Watch | SPC | Audrain, Barry, Boone, Callaway, Camden, Christian and 41 more | 6 hr |
| Oct 17, 6:19 PM CDT | Mesoscale Discussion | SPC | Carter, Iron, Madison, Oregon, Perry, Reynolds and 3 more | 56 min |
Nearby
Mesoscale Discussions in Missouri, 2012Mesoscale Discussions in Arkansas, 2012Every mesoscale discussion in 2012
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.