Alert archive / Utah / Mesoscale Discussions in 2007
Mesoscale Discussion 39
The Storm Prediction Center issued this mesoscale discussion at Jan 11, 2007, 11:28 AM MST for 8 counties in Utah; 6 counties in Wyoming. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Jan 11, 2007, 11:28 AM MST (18:28 UTC)
- Expired
- Jan 11, 2007, 4:30 PM MST
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
Counties Cache County, UT, Daggett County, UT, Davis County, UT, Morgan County, UT, Rich County, UT, Salt Lake County, UT, Summit County, UT, Weber County, UT, Carbon County, WY, Converse County, WY, Lincoln County, WY, Natrona County, WY, Sweetwater County, WY, Uinta County, WY
The radar
The Riverton/Lander radar (KRIW), 138 km from the middle of the area, began a volume at 18:29 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
Riverton, WY (KRIW), launched 12:00Z, 6.5 hours before the alert went out and 140 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
- 734 m above ground
- 0-6 km bulk shear
- 93 kt
- 0-1 km storm-relative helicity
- 219 m²/s²
- 0-3 km storm-relative helicity
- 331 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 ACUS11 KWNS 111828 SWOMCD SPC MCD 111828 WYZ000-UTZ000-IDZ000-112330- MESOSCALE DISCUSSION 0039 NWS STORM PREDICTION CENTER NORMAN OK 1228 PM CST THU JAN 11 2007 AREAS AFFECTED...NRN UT/SRN AND SCNTRL WY CONCERNING...HEAVY SNOW VALID 111828Z - 112330Z MODERATE TO HEAVY SNOW WILL CONTINUE THIS AFTN FROM THE WASATCH RANGE NEWD TO SCNTRL/SRN WY. HOURLY SNOW RATES OF 2 INCHES ARE LIKELY WITH BLIZZARD CONDITIONS POSSIBLE IN THE HIGHER ELEVATIONS AND OPEN AREAS... LATEST SFC ANALYSIS SHOWS SECONDARY SURGE OF COLD AIR ACROSS CNTRL WY...WITH COLD FRONT EXTENDING FROM NEAR ROCK SPRINGS TO SOUTH OF PROVO. TEMPERATURES HAVE PLUMMETED NORTH OF THE BOUNDARY WITH LATEST OBSERVATIONS AT CASPER AND LANDER AROUND 20 DEGREES COLDER SINCE EARLY MORNING. VISIBLE SATELLITE LOOPS SHOW THE CONVECTIVE NATURE OF THE MAIN SNOW BAND NOW FROM SLC TO CPR. MORNING SOUNDING FROM SLC SHOWS JUST A SLIVER OF INSTABILITY WITH STEEP MID LEVEL LAPSE RATES /AROUND 8 DEG C PER KM/ . PROLONGED PERIOD OF HEAVY SNOW SEEMS LIKELY TODAY...AS NOSE OF 80 KT MID LEVEL JET APPROACHES THE AREA. LOW/MID LEVEL CONVERGENCE WILL BE MAXIMIZED ALONG AND NORTH OF ARCTIC BOUNDARY AND THIS COMBINED WITH UPSLOPE FLOW WILL FAVOR HEAVY SNOW RATES THIS AFTN. SNOW RATES MAY ALSO BE CONVECTIVELY ENHANCED AS FORECAST SOUNDINGS DOWNSTREAM ACROSS NW CO AND NEAR THE WY/CO SHOW INSTABILITY /WHERE SFC TEMPS ARE STILL IN THE 30S/. IN ADDITION...THE UNIDIRECTIONAL WIND PROFILE WILL CONTINUE TO SUPPORT BACK BUILDING BANDS OF SNOW. AS UPPER LOW DIGS SWD ACROSS THE GREAT BASIN LATER...HEAVIEST SNOW BAND WILL MOVE SEWD INTO NW CO/CNTRL PORTIONS OF UT LATER TONIGHT. ..TAYLOR.. 01/11/2007 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ...NOTICE... SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A SCHEDULED BASIS FROM DECEMBER 1 THROUGH FEBRUARY 28...FOUR TIMES A DAY...AROUND 00 UTC...06 UTC...12 UTC...AND 18 UTC FOR SIGNIFICANT SHORT RANGE WINTER WEATHER EVENTS. ATTN...WFO...CYS...RIW...GJT...SLC...PIH... 41440759 40271153 40891231 41461232 41961175 43020864 43440672 42890524 41920549
Nearby
Mesoscale Discussions in Utah, 2007Mesoscale Discussions in Wyoming, 2007Every mesoscale discussion in 2007
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.