Alert archive / Missouri / Mesoscale Discussions in 2017
Mesoscale Discussion 433
The Storm Prediction Center issued this mesoscale discussion at Apr 4, 2017, 7:40 PM CDT for 5 counties in Missouri. It was in force for 65 min.
The area
The outline as issued.
The facts
- Issued
- Apr 4, 2017, 7:40 PM CDT (00:40 UTC)
- Expired
- Apr 4, 2017, 8:45 PM CDT
- In force
- 65 min
- Issued by
- the Storm Prediction Center
Counties Barry County, MO, Christian County, MO, Greene County, MO, Lawrence County, MO, Stone County, MO
The radar
The Springfield radar (KSGF), 44 km from the middle of the area, began a volume at 00:39 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 00:00Z, 0.7 hours before the alert went out and 8 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
- 326 J/kg
- Mixed-layer CIN
- -51 J/kg
- Mixed-layer LCL
- 1384 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- 312 m²/s²
- 0-3 km storm-relative helicity
- 743 m²/s²
- Significant tornado parameter
- 1.0
- Supercell composite
- 12.5
The text
As transmitted.
759 ACUS11 KWNS 050041 SWOMCD SPC MCD 050040 MOZ000-050145- Mesoscale Discussion 0433 NWS Storm Prediction Center Norman OK 0740 PM CDT Tue Apr 04 2017 Areas affected...Southwest MO Concerning...Severe Thunderstorm Watch 121... Valid 050040Z - 050145Z The severe weather threat for Severe Thunderstorm Watch 121 continues. SUMMARY...A semi-focused damaging wind/some tornado risk should continue to develop northeastward through 01Z-02Z (8-9pm CDT) across southwest MO, including the I-44 corridor from near the Mount Vernon area northeastward toward the Springfield metro. A spatial extension of the existing watch will be necessary. DISCUSSION...A strong supercell with a history of probable tornado damage near Goodman MO continues to steadily progress northeastward across southwest MO, approaching I-44 and the Mount Vernon MO vicinity as of 730 pm CDT. While the background environment is not overly moist or unstable amidst only lower 50s F surface dewpoints, adequate low-level moisture/buoyancy exists coincident with a corridor of strong low-level shear and 3+ mb/2-hour pressure falls near a warm front as it parallels I-44 through the Springfield area. While the the longevity of a semi-discrete-supercell-related tornado risk is not certain, an impactful severe risk (damaging winds at the very least) should continue to favor the warm front including areas near/south of I-44 and the Springfield metro through mid-evening. ..Guyer.. 04/05/2017 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGF... LAT...LON 36529411 36939423 37429376 37509304 36749312 36529411
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 4, 9:12 PM CDT | Severe Thunderstorm Watch | SPC | Christian, Dent, Douglas, Howell, Laclede, Oregon and 8 more | 4 hr |
| Apr 4, 9:28 PM CDT | Mesoscale Discussion | SPC | Christian, Dallas, Dent, Douglas, Greene, Howell and 11 more | 92 min |
| Apr 4, 11:38 PM CDT | Mesoscale Discussion | SPC | Carter, Crawford, Dent, Howell, Iron, Madison and 7 more | 97 min |
Nearby
Mesoscale Discussions in Missouri, 2017Every mesoscale discussion in 2017
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.