Alert archive / Utah / Mesoscale Discussions in 2016

Mesoscale Discussion 177

March 6, 20167 counties in Utah

The Storm Prediction Center issued this mesoscale discussion at Mar 6, 2016, 4:35 PM MST for 7 counties in Utah. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Mar 6, 2016, 4:35 PM MST (23:35 UTC)
Expired
Mar 6, 2016, 7:00 PM MST
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
5%

Counties Garfield County, UT, Kane County, UT, Piute County, UT, Sanpete County, UT, Sevier County, UT, Utah County, UT, Wayne County, UT

The radar

The Cedar City radar (KICX), 93 km from the middle of the area, began a volume at 23:35 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

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 11.6 hours before the alert went out and 284 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, Flgstf/Belemont, AZ at 12:00Z on 2016-03-06Temperature 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 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2016-03-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 265 square meters per square second.19395878Sfc1 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
1372 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
265 m²/s²
0-3 km storm-relative helicity
300 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

932 
ACUS11 KWNS 062335
SWOMCD
SPC MCD 062335 
UTZ000-AZZ000-070200-

MESOSCALE DISCUSSION 0177
NWS STORM PREDICTION CENTER NORMAN OK
0535 PM CST SUN MAR 06 2016

AREAS AFFECTED...PARTS OF CENTRAL UT TO NORTHERN AZ

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 062335Z - 070200Z

PROBABILITY OF WATCH ISSUANCE...5 PERCENT

SUMMARY...LOCALLY STRONG WIND GUSTS EXCEEDING 40-50 KT WILL REMAIN
POSSIBLE INTO THE EARLY EVENING ACROSS CENTRAL UT TO NORTHERN AZ. 
THESE STRONGER WINDS WILL TEND TO BE ASSOCIATED WITH THUNDERSTORMS
THAT DEVELOP ALONG THE EASTWARD-MOVING COLD FRONT ACROSS THE
DISCUSSION AREA.

DISCUSSION...WATER VAPOR IMAGERY SHOWED THE LEADING PORTION OF
UPWARD-VERTICAL MOTION ASSOCIATED WITH A PROGRESSIVE GREAT BASIN
SHORTWAVE TROUGH JUXTAPOSED WITH THE ATTENDANT COLD FRONT ADVANCING
E/SEWD ACROSS NORTHERN AND WESTERN UT TO FAR SOUTHERN NV DURING THE
LATE AFTERNOON.  ADDITIONAL SURFACE HEATING PRECEDING THE COLD FRONT
/PER VISIBLE SATELLITE IMAGERY SHOWING BREAKS IN CLOUDS/ WILL
SUSTAIN A MARGINALLY UNSTABLE ENVIRONMENT AND STEEP SURFACE-3 KM
LAPSE RATES /EXCEEDING 7-8 C PER KM/.  THIS COMBINED WITH UPLIFT
ALONG THE COLD FRONT AND FORCING ALOFT WITH THE SHORTWAVE TROUGH
WILL SUPPORT ADDITIONAL TSTM DEVELOPMENT.  STRONG SWLY WINDS OF
40-45 KT IN THE LOWER TROPOSPHERE WERE SAMPLED BY VWP DATA AT LAS
VEGAS AND IN SOUTHWEST UT PRIOR TO FRONTAL PASSAGE.  GIVEN THE
PRESENCE OF STEEP LOW-LEVEL LAPSE RATES AND STRONGER PRE-FRONTAL
LOW-LEVEL WINDS...ISOLATED STRONG TO SEVERE WIND GUSTS WILL BE
POSSIBLE WITH TSTM DOWNDRAFTS.  

THE EVENTUAL LOSS OF DAY TIME HEATING WILL RESULT IN A DECREASE IN
LOW-LEVEL LAPSE RATES THIS EVENING AND LIMIT THE EASTWARD EXTENT OF
STRONG WIND GUSTS...AS THE COLD FRONT REACHES EASTERN UT AND
NORTHEAST TO CENTRAL AZ LATER THIS EVENING.

..PETERS/WEISS.. 03/06/2016

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

ATTN...WFO...GJT...FGZ...SLC...VEF...

LAT...LON   36371295 37811326 39531260 40181216 40211162 39971145
            39431093 38591064 37851059 37471063 36651086 36181143
            35931192 35931258 36011284 36371295

Nearby

Mesoscale Discussions in Utah, 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.