Alert archive / Iowa / Mesoscale Discussions in 2016

Mesoscale Discussion 971

June 17, 20167 counties in Iowa

The Storm Prediction Center issued this mesoscale discussion at Jun 17, 2016, 7:23 PM CDT for 7 counties in Iowa. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Jun 17, 2016, 7:23 PM CDT (00:23 UTC)
Expired
Jun 17, 2016, 9:30 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Cerro Gordo County, IA, Emmet County, IA, Hancock County, IA, Kossuth County, IA, Palo Alto County, IA, Winnebago County, IA, Worth County, IA

The radar

The Des Moines radar (KDMX), 170 km from the middle of the area, began a volume at 00:23 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

Minneapolis, MN (KMPX), launched 00:00Z, 0.4 hours before the alert went out and 185 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.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2016-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 380 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 00:00Z on 2016-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
380 J/kg
Mixed-layer CIN
-89 J/kg
Mixed-layer LCL
1117 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
148 m²/s²
Significant tornado parameter
0.1
Supercell composite
2.8

Open this sounding in Storm Lab

The text

As transmitted.

103 
ACUS11 KWNS 180023
SWOMCD
SPC MCD 180023 
IAZ000-180230-

MESOSCALE DISCUSSION 0971
NWS STORM PREDICTION CENTER NORMAN OK
0723 PM CDT FRI JUN 17 2016

AREAS AFFECTED...NCNTRL IA

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 180023Z - 180230Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...SOME THREAT FOR MAINLY A FEW STRONG WIND GUSTS WILL EXIST
OVER NCNTRL IA THIS EVENING...BUT OVERALL THREAT IS EXPECTED TO
REMAIN TOO LIMITED FOR A WW.

DISCUSSION...LINE OF STORMS OVER SRN MN CONTINUES TO PROPAGATE SWD
ALONG A PROGRESSIVE OUTFLOW BOUNDARY. OVERALL TREND HAS BEEN FOR THE
LINE TO BECOME LESS ORGANIZED WITH TIME WITH THE CONVECTIVE OUTFLOW
SURGING AHEAD OF THE HEAVIER RAIN CORES...SUGGESTING INCREASINGLY
TILTED UPDRAFTS. TEMPERATURES ACROSS NCNTRL IA ARE IN THE LOW 80S
WITH MID 60S F DEWPOINTS SUPPORTING MODERATE INSTABILITY...BUT
CONVECTIVE INHIBITION IS EXPECTED TO BECOME PROBLEMATIC WITH THE
ONSET OF NOCTURNAL COOLING. IN THE MEANTIME...SFC OBSERVATIONS
CONTINUE TO SHOW MOSTLY SUB SEVERE WIND GUSTS UP TO 45 KT...AND
MARGINALLY SEVERE GUSTS WILL REMAIN POSSIBLE AS ACTIVITY CROSSES
INTO NCNTRL IA BEFORE FURTHER WEAKENING OCCURS.

..DIAL/THOMPSON.. 06/18/2016

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

ATTN...WFO...DMX...

LAT...LON   43369478 43479411 43389317 42949320 42899475 43369478

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 17, 8:57 PM CDTMesoscale DiscussionSPCCherokee, Plymouth, Sioux, Woodbury63 min

Nearby

Mesoscale Discussions in Iowa, 2016Every mesoscale discussion in 2016

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.