Alert archive / Wisconsin / Mesoscale Discussions in 2003

Mesoscale Discussion 342

March 27, 20038 counties in Michigan; 10 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Mar 27, 2003, 3:36 PM EST for 8 counties in Michigan; 10 counties in Wisconsin. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Mar 27, 2003, 3:36 PM EST (20:36 UTC)
Expired
Mar 27, 2003, 8:30 PM EST
In force
5 hr
Issued by
the Storm Prediction Center

Counties Baraga County, MI, Dickinson County, MI, Gogebic County, MI, Houghton County, MI, Iron County, MI, Keweenaw County, MI, Marquette County, MI, Ontonagon County, MI, Ashland County, WI, Bayfield County, WI, Florence County, WI, Forest County, WI, Iron County, WI, Oneida County, WI, Price County, WI, Sawyer County, WI, Vilas County, WI, Washburn County, WI

The radar

The Marquette radar (KMQT), 139 km from the middle of the area, began a volume at 20:39 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 nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 8.6 hours before the alert went out and 200 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, Green Bay/Straub, WI at 12:00Z on 2003-03-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Green Bay/Straub, WI at 12:00Z on 2003-03-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 94 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1160 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
94 m²/s²
0-3 km storm-relative helicity
272 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

671 
ACUS11 KWNS 272036
SWOMCD
SPC MCD 272036 
MIZ000-WIZ000-280130-

MESOSCALE DISCUSSION 0342
NWS STORM PREDICTION CENTER NORMAN OK
0236 PM CST THU MAR 27 2003

AREAS AFFECTED...NRN WI AND CENTRAL/WRN UPPER MI

CONCERNING...HEAVY SNOW 

VALID 272036Z - 280130Z

POTENTIAL EXISTS FOR 1/HR SNOWFALL RATES BEGINNING THIS EVENING
AND CONTINUING INTO THE OVERNIGHT PERIOD ACROSS NRN WI AND
CENTRAL/WRN UPPER MI. MODERATE TO LOCALLY HEAVY WET SNOW WILL
OVERSPREAD THE DISCUSSION AREA FROM SW-NE BETWEEN 27/22Z-28/02Z.



STRONG 700MB TROUGH/LOW CENTER PRESENTLY OVER WRN IA IS EXPECTED
TO TRACK NEWD TO N-CENTRAL WI BY 28/12Z WITHIN AN INTENSIFYING
BAROCLINIC ZONE. THE 700MB DEFORMATION ZONE AND ASSOCIATED
FRONTOGENETIC FORCING CORRESPONDING TO MODERATE/HEAVY
PRECIPITATION AREA ACROSS SERN MN AND WRN WI AT 27/2030Z IS
EXPECTED TO TRANSLATE NEWD WITH THE SYNOPTIC LOW ALLOWING FOR A
SIGNIFICANT INCREASE IN MID-TROPOSPHERIC UVV ACROSS THE
DISCUSSION AREA THIS EVENING INTO THE OVERNIGHT PERIOD. ETA MODEL
FORECAST SOUNDINGS SUGGEST A HEAVY/WET SNOWFALL WITH SURFACE
TEMPERATURES COOLING DIABATICALLY TO NEAR OR JUST SLIGHTLY BELOW
FREEZING ACROSS THE REGION AS STEADY PRECIPITATION COMMENCES FROM
SW TO NE OVER NRN/NWRN WI AND WRN/CENTRAL UPPER MI. A MIX OF
RAIN/SNOW IS POSSIBLE EARLY OWING TO MARGINAL BOUNDARY LAYER
TEMPERATURES. 



STEEP MID-LEVEL LAPSE RATES WILL CONTRIBUTE TO MINIMAL
CAPE/SLIGHTLY NEGATIVE EPV VALUES AFTER 00Z...WITH NEAR
SATURATION IN DENDRITE GROWTH LAYER /-12C TO -16C/ FAVORABLE FOR
HEAVY SNOW DEVELOPMENT/ACCUMULATION BEGINNING THIS EVENING.
PRESENT TRENDS SUGGEST THE AXIS OF HEAVIEST/MOST PERSISTENT SNOW
FROM 60 SW IWD TO NEAR MQT DURING THE 28/00-06Z PERIOD.

..BANACOS.. 03/27/2003

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

ATTN...WFO...MQT...GRB...DLH...MPX...

45758739 45568799 45548880 45568988 45649140 45779197
46599174 47129013 47508777 46178723

Nearby

Mesoscale Discussions in Wisconsin, 2003Mesoscale Discussions in Michigan, 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.