Alert archive / Idaho / Mesoscale Discussions in 2012

Mesoscale Discussion 583

April 24, 20129 counties in Idaho

The Storm Prediction Center issued this mesoscale discussion at Apr 24, 2012, 1:18 PM MDT for 9 counties in Idaho. It was in force for 87 min.

The area

The outline as issued.

The facts

Issued
Apr 24, 2012, 1:18 PM MDT (19:18 UTC)
Expired
Apr 24, 2012, 2:45 PM MDT
In force
87 min
Issued by
the Storm Prediction Center

Counties Adams County, ID, Clearwater County, ID, Gem County, ID, Idaho County, ID, Latah County, ID, Lewis County, ID, Nez Perce County, ID, Valley County, ID, Washington County, ID

The radar

The Pendleton radar (KPDT), 215 km from the middle of the area, began a volume at 19:19 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

Boise Airport, ID (KBOI), launched 12:00Z, 7.3 hours before the alert went out and 225 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, Boise Airport, ID at 12:00Z on 2012-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 16 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, Boise Airport, ID at 12:00Z on 2012-04-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -74 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
16 J/kg
Mixed-layer CIN
-330 J/kg
Mixed-layer LCL
1609 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
-74 m²/s²
0-3 km storm-relative helicity
3 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.

881 
ACUS11 KWNS 241919
SWOMCD
SPC MCD 241918
IDZ000-MTZ000-ORZ000-WAZ000-242045-

MESOSCALE DISCUSSION 0583
NWS STORM PREDICTION CENTER NORMAN OK
0218 PM CDT TUE APR 24 2012

AREAS AFFECTED...NE ORE...ID...SE WA...FAR WRN MT

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 241918Z - 242045Z

AS THUNDERSTORM DEVELOPMENT INCREASES ACROSS THE NRN ROCKIES...HAIL
AND ISOLATED WIND DAMAGE MAY OCCUR WITH THE MORE INTENSE CELLS. THE
THREATS ARE EXPECTED TO REMAIN MARGINAL AND WW ISSUANCE IS NOT
ANTICIPATED.

THUNDERSTORMS ARE BEGINNING TO INITIATE ACROSS NCNTRL ID WHERE
MESOANALYSIS SHOWS MODERATE INSTABILITY IN PLACE WITH MLCAPE VALUES
ESTIMATED IN THE 1000 TO 1500 J/KG RANGE. IN ADDITION...REGIONAL
WSR-88D VWPS SHOW ABOUT 30 KT OF DEEP LAYER SHEAR. THIS COMBINED
WITH LAPSE RATES OF 8.0 TO 9.0 C/KM SHOULD BE ENOUGH FOR STRONG
UPDRAFTS CAPABLE OF PRODUCING HAIL. ALSO...SFC TEMPERATURE-DEWPOINT
SPREADS OF 30 TO 40 DEGREES MAY HELP ENHANCE DOWNDRAFT STRENGTH
ENOUGH FOR ISOLATED WIND DAMAGE OVER THE NEXT FEW HOURS.
HOWEVER...THE MCD AREA IS LOCATED JUST TO THE WEST OF THE RIDGE AXIS
WHICH SHOULD KEEP STORM ORGANIZATION ON THE MARGINAL SIDE THIS
AFTERNOON.

..BROYLES.. 04/24/2012

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

ATTN...WFO...MSO...BOI...OTX...PDT...

LAT...LON   46171447 47001477 47311558 47151687 46531726 45621713
            45101752 44541771 44161721 44021658 44141604 44871508
            45451450 46171447

Nearby

Mesoscale Discussions in Idaho, 2012Every mesoscale discussion in 2012

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.