Alert archive / Michigan / Mesoscale Discussions in 2003
Mesoscale Discussion 1925
The Storm Prediction Center issued this mesoscale discussion at Jul 20, 2003, 9:39 PM EST for 9 counties in Indiana; 18 counties in Michigan. It was in force for 66 min.
The area
The outline as issued.
The facts
- Issued
- Jul 20, 2003, 9:39 PM EST (02:39 UTC)
- Expired
- Jul 20, 2003, 10:45 PM EST
- In force
- 66 min
- Issued by
- the Storm Prediction Center
All 27 counties
Elkhart County, IN, Kosciusko County, IN, LaGrange County, IN, LaPorte County, IN, Marshall County, IN, Noble County, IN, Saint Joseph County, IN, Starke County, IN, Steuben County, IN, Allegan County, MI, Barry County, MI, Berrien County, MI, Branch County, MI, Calhoun County, MI, Cass County, MI, Eaton County, MI, Ionia County, MI, Kalamazoo County, MI, Kent County, MI, Mecosta County, MI, Montcalm County, MI, Muskegon County, MI, Newaygo County, MI, Oceana County, MI, Ottawa County, MI, Saint Joseph County, MI, Van Buren County, MI
The radar
The Grand Rapids radar (KGRR), 56 km from the middle of the area, began a volume at 02:43 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
Detroit, MI (KDTX), launched 00:00Z, 2.7 hours before the alert went out and 195 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
- 1227 J/kg
- Mixed-layer CIN
- -2 J/kg
- Mixed-layer LCL
- 788 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 142 m²/s²
- 0-3 km storm-relative helicity
- 156 m²/s²
- Significant tornado parameter
- 0.8
- Supercell composite
- 4.7
The text
As transmitted, in the capitals the NWS used until 2016.
750 ACUS11 KWNS 210239 SWOMCD SPC MCD 210239 MIZ000-INZ000-210345- MESOSCALE DISCUSSION 1925 NWS STORM PREDICTION CENTER NORMAN OK 0939 PM CDT SUN JUL 20 2003 AREAS AFFECTED...WRN LOWER MI THROUGH NRN IND CONCERNING...SEVERE THUNDERSTORM WATCH 776... VALID 210239Z - 210345Z OVERALL SEVERE THREAT APPEARS TO HAVE DECREASED OVER NRN HALF OF WW 776. BEST CHANCE FOR ADDITIONAL SEVERE WEATHER APPEARS TO BE OVER SRN LOWER MI INTO NRN IND. ISOLATED STORM OVER SRN LOWER MI HAS MOVED E OF WW 776 AND ATMOSPHERE ACROSS NRN LOWER MI HAS BEEN STABILIZED SOMEWHAT. THUS STORMS DEVELOPING UPSTREAM OVER LAKE MI AND ERN WI WILL NOT LIKELY MAINTAIN THEIR INTENSITY AS THEY CONTINUE SEWD. HOWEVER...WARM ADVECTION IS EXPECTED TO INCREASE ALONG INSTABILITY GRADIENT ACROSS NRN IND THIS EVENING AS SWLY LOW LEVEL JET INTENSIFIES IN RESPONSE TO UPPER JET MOVING SEWD INTO THE UPPER MS VALLEY. LATEST RADAR SHOW A FEW CELLS ALREADY DEVELOPING OVER NRN IL AND SRN LAKE MI.LARGE HAIL AND DAMAGING WIND WILL CONTINUE TO BE THE MAIN THREATS. ..DIAL.. 07/21/2003 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...IWX...GRR... 41058678 42378677 43948655 43828553 43628482 42978475 41768491 41208511
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 9:48 PM EST | Mesoscale Discussion | SPC | Lake, Newton | 117 min |
| Jul 20, 10:15 PM EST | Severe Thunderstorm Watch | SPC | Lake, Porter | 7 hr |
| Jul 20, 11:45 PM EST | Severe Thunderstorm Watch | SPC | Allen, DeKalb, Elkhart, Fulton, Huntington, Kosciusko and 11 more | 5 hr |
| Jul 21, 1:56 AM EST | Mesoscale Discussion | SPC | Bartholomew, Benton, Boone, Brown, Clay, Clinton and 20 more | 2 hr |
| Jul 21, 3:15 AM EST | Severe Thunderstorm Watch | SPC | Adams, Allen, Benton, Blackford, Boone, Carroll and 47 more | 6 hr |
| Jul 21, 4:12 AM EST | Mesoscale Discussion | SPC | Gibson, Knox, Posey, Sullivan, Vanderburgh | 2 hr |
| Jul 21, 5:03 AM EST | Mesoscale Discussion | SPC | Bartholomew, Brown, Clark, Crawford, Daviess, Dearborn and 17 more | 117 min |
| Jul 21, 5:10 AM EST | Severe Thunderstorm Watch | SPC | Dearborn, Decatur, Fayette, Franklin, Jay, Jefferson and 9 more | 6 hr |
| Jul 21, 10:27 AM EST | Mesoscale Discussion | SPC | Bartholomew, Brown, Clark, Crawford, Daviess, Dearborn and 29 more | 2 hr |
| Jul 21, 3:26 PM EST | Mesoscale Discussion | SPC | Allen, DeKalb, Elkhart, Fulton, Jasper, Kosciusko and 12 more | 94 min |
| Jul 21, 9:59 AM EST | Mesoscale Discussion | SPC | Allegan, Barry, Bay, Clare, Clinton, Eaton and 21 more | 2 hr |
Nearby
Mesoscale Discussions in Michigan, 2003Mesoscale Discussions in Indiana, 2003Every mesoscale discussion in 2003
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.