Alert archive / Wisconsin / Mesoscale Discussions in 2017
Mesoscale Discussion 32
The Storm Prediction Center issued this mesoscale discussion at Jan 11, 2017, 3:07 PM CST for 19 counties in Wisconsin. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Jan 11, 2017, 3:07 PM CST (21:07 UTC)
- Expired
- Jan 11, 2017, 7:00 PM CST
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
Counties Brown County, WI, Calumet County, WI, Columbia County, WI, Dane County, WI, Dodge County, WI, Fond du Lac County, WI, Grant County, WI, Green County, WI, Green Lake County, WI, Iowa County, WI, Jefferson County, WI, Lafayette County, WI, Marquette County, WI, Ozaukee County, WI, Sauk County, WI, Sheboygan County, WI, Washington County, WI, Waukesha County, WI, Winnebago County, WI
The radar
The Milwaukee radar (KMKX), 49 km from the middle of the area, began a volume at 21:11 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
Green Bay/Straub, WI (KGRB), launched 12:00Z, 9.1 hours before the alert went out and 151 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 807 m above ground
- 0-6 km bulk shear
- 90 kt
- 0-1 km storm-relative helicity
- 144 m²/s²
- 0-3 km storm-relative helicity
- 465 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
387
ACUS11 KWNS 112107
SWOMCD
SPC MCD 112107
WIZ000-ILZ000-IAZ000-120100-
Mesoscale Discussion 0032
NWS Storm Prediction Center Norman OK
0307 PM CST Wed Jan 11 2017
Areas affected...Southern WI and far northwestern IL
Concerning...Winter mixed precipitation
Valid 112107Z - 120100Z
SUMMARY...A mix of freezing rain, sleet, and snow is anticipated
over the next few hours across portions of southern WI and far
northwestern IL. Freezing rain rates could briefly approach 0.05
inch per hour with transient snowfall rates near 1 inch per hour
also possible farther north of the transition zone.
DISCUSSION...Recent surface analysis places a cold front from near
the easternmost WI/IL border southwestward through central MO and
into southeastern KS. Southwesterly flow aloft continues above this
frontal zone, with the resulting isentropic lift supporting the
development of precipitation across eastern IA, southern WI, and
northwestern IL. This process is expected to continue, with the
light precipitation acting to moisten the mid-level dry layer noted
on recent RAP forecast soundings. Once this dry layer is overcome,
more substantial precipitation will begin to reach the surface, with
profiles across southern portions of the area currently supporting a
mix of freezing rain and sleet. Freezing rain rates may briefly
exceed 0.05 inch per hour. Farther north, colder profiles will
result in snow as the primary precipitation type, with snowfall
rates briefly exceeding one inch per hour possible.
..Mosier.. 01/11/2017
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GRB...MKX...DVN...ARX...
LAT...LON 43378780 43028819 42648929 42349032 42499066 42999079
43918977 44688749 43948769 43378780Nearby
Mesoscale Discussions in Wisconsin, 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.