Alert archive / Mississippi / Mesoscale Discussions in 2020
Mesoscale Discussion 1513
The Storm Prediction Center issued this mesoscale discussion at Aug 16, 2020, 5:05 PM CDT for 15 counties in Mississippi. It was in force for 85 min.
The area
The outline as issued.
The facts
- Issued
- Aug 16, 2020, 5:05 PM CDT (22:05 UTC)
- Expired
- Aug 16, 2020, 6:30 PM CDT
- In force
- 85 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
Counties Attala County, MS, Clarke County, MS, Copiah County, MS, Covington County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Leake County, MS, Madison County, MS, Neshoba County, MS, Newton County, MS, Rankin County, MS, Scott County, MS, Simpson County, MS, Smith County, MS
The radar
The Jackson/Brandon,MS radar (KDGX), 42 km from the middle of the area, began a volume at 22:08 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 nearest sounding before it
Jackson, MS (KJAN), launched 12:00Z, 10.1 hours before the alert went out and 50 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
- 1044 J/kg
- Mixed-layer CIN
- -97 J/kg
- Mixed-layer LCL
- 1241 m above ground
- 0-6 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 22 m²/s²
- 0-3 km storm-relative helicity
- 66 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
313 ACUS11 KWNS 162205 SWOMCD SPC MCD 162205 MSZ000-162330- Mesoscale Discussion 1513 NWS Storm Prediction Center Norman OK 0505 PM CDT Sun Aug 16 2020 Areas affected...Central Mississippi Concerning...Severe potential...Watch unlikely Valid 162205Z - 162330Z Probability of Watch Issuance...20 percent SUMMARY...Isolated damaging downbursts are possible the next few hours. At this time a severe thunderstorm watch does not appear warranted. DISCUSSION...A few small clusters of strong convection have developed ahead of a weak surface front over central MS. This activity is primarily driven by strong boundary-layer heating which allowed low-level lapse rates to steepen in excess of 8 C/km, resulting in MLCAPE values on the order of 3500 J/kg. Latest water-vapor imagery suggests a few weak mid-level eddies are drifting south-southwest along the frontal zone which may be encouraging this activity, and possible extend its longevity through the early evening hours. With high-PW air mass, the primary concern is local wet micro bursts. ..Darrow/Guyer.. 08/16/2020 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MOB...JAN... LAT...LON 33288971 32208848 31408928 31709055 33288971
Nearby
Mesoscale Discussions in Mississippi, 2020Every mesoscale discussion in 2020
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.