Mesoscale Discussion 830

Issued

Jun 6, 2016, 12:18 PM EDT (16:18 UTC)

Expired

Jun 6, 2016, 2:45 PM EDT

In force

2 hr

Issued by

the Storm Prediction Center

Chance of a watch

60%

The Grand Rapids radar (KGRR), 32 km from the middle of the area, began a volume at 16:19 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.

269 
ACUS11 KWNS 061619
SWOMCD
SPC MCD 061618 
MIZ000-061845-

MESOSCALE DISCUSSION 0830
NWS STORM PREDICTION CENTER NORMAN OK
1118 AM CDT MON JUN 06 2016

AREAS AFFECTED...PORTIONS OF CNTRL AND SRN LOWER MICHIGAN AND LAKE
MICHIGAN

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 061618Z - 061845Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...FAST-MOVING TSTMS WITH DMGG-WIND POTENTIAL WILL LIKELY
MOVE ACROSS THE AREA THIS AFTERNOON...AND THE ISSUANCE OF A SEVERE
THUNDERSTORM WATCH MAY BE REQUIRED EARLY THIS AFTERNOON.

DISCUSSION...ORGANIZED CONVECTION HAS ALREADY DEVELOPED ACROSS
PORTIONS OF E-CNTRL WI IMMEDIATELY IN ADVANCE OF A MID-LEVEL VORT
MAX ORBITING AROUND THE SWRN RIM OF A DEEP CYCLONE CENTERED OVER WRN
QUEBEC. FORWARD EXTRAPOLATION OF THE VORT MAX TAKES IT ON A PATH
REACHING NEAR DETROIT AROUND 20Z/21Z AND NEAR CLEVELAND OHIO AROUND
22Z/23Z. THIS SUGGESTS THAT DCVA WILL SPREAD ACROSS THE REGION NEAR
AND PRIOR TO PEAK HEATING. DESPITE ONLY LIMITED LOW-LEVEL MOISTURE
AVAILABLE -- E.G. DEWPOINTS IN THE LOWER/MIDDLE 50S -- STEEPENING
LOW/MID-LEVEL LAPSE RATES WITH ADIABATIC COOLING ALOFT RELATED TO
THE DCVA WILL SUPPORT SUFFICIENT BUOYANCY FOR TSTM INTENSIFICATION
THIS AFTERNOON. 

UPSTREAM VWPS AT GRB AND MKX SAMPLE DEEP UNIDIRECTIONAL FLOW WITH
WLYS AT 30-45 KT THROUGH THE LOWER/MIDDLE PORTION OF THE CONVECTIVE
LAYER. THIS KINEMATIC PROFILE SUPPORTING ELONGATED STRAIGHT
HODOGRAPHS...COMBINED WITH AMPLE HIGH-LEVEL FLOW ENHANCING
CONVECTIVE VENTILATION...SUGGESTS THAT SPLITTING TSTMS AND
FAST-MOVING CONVECTIVE CLUSTERS WILL LIKELY SPREAD ACROSS THE REGION
DURING THE AFTERNOON HOURS. THE RELATIVELY DRY THERMODYNAMIC
PROFILES WILL ENCOURAGE EVAPORATIONAL COOLING TO ACCELERATE
DOWNDRAFTS AND CONVECTIVE MOMENTUM TRANSPORT...FACILITATING THE
POTENTIAL FOR DMGG WIND GUSTS. ISOLATED SVR HAIL MAY ALSO OCCUR
GIVEN COOLING PROFILES ALOFT AND ANTICIPATED SPLITTING TSTMS. THERE
IS SOME UNCERTAINTY REGARDING THE TIMING OF THE MORE ROBUST INCREASE
IN SVR POTENTIAL WHICH EXTENDS TO POSSIBLE WW ISSUANCE...THOUGH THE
SVR RISK WILL LIKELY INCREASE THIS AFTERNOON.

..COHEN/WEISS.. 06/06/2016

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

ATTN...WFO...DTX...APX...IWX...GRR...

LAT...LON   41918563 42188665 42988734 43738706 43888646 43928554
            43958380 44008281 42748269 41938351 41918563

Mesoscale Discussions in Michigan, 2016Every mesoscale discussion in 2016

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.