Alert archive / Nevada / Mesoscale Discussions in 2021

Mesoscale Discussion 623

May 15, 20214 counties in Nevada

The Storm Prediction Center issued this mesoscale discussion at May 15, 2021, 1:56 PM PDT for 4 counties in Nevada. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued: May 15, 2021, 1:56 PM PDT (20:56 UTC)
Expired: May 15, 2021, 3:30 PM PDT
In force: 94 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 20%

Counties Churchill County, NV, Eureka County, NV, Lander County, NV, Pershing County, NV

The radar

The Elko radar (KLRX), 130 km from the middle of the area, began a volume at 21:00 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

Reno, NV (KREV), launched 12:00Z, 8.9 hours before the alert went out and 79 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 3037 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 2 m²/s²
0-3 km storm-relative helicity: 96 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

858 
ACUS11 KWNS 152056
SWOMCD
SPC MCD 152056 
NVZ000-152230-

Mesoscale Discussion 0623
NWS Storm Prediction Center Norman OK
0356 PM CDT Sat May 15 2021

Areas affected...Central Nevada

Concerning...Severe potential...Watch unlikely 

Valid 152056Z - 152230Z

Probability of Watch Issuance...20 percent

SUMMARY...Thunderstorms developing beneath an upper-level low may
produce occasional severe wind gusts or hail through this evening.
Trends will be monitored, but a weather watch is not expected.

DISCUSSION...Thunderstorm coverage and intensity has steadily
increased over the last half hour across portions of central Nevada
as stronger ascent from the upper low across the Great Basin has
moved overhead. Additional strong/severe storm development appears
likely late this afternoon and into the evening with the risk of
large hail and damaging winds. Dewpoints in the 30s and 40s F
underneath a pocket of -17 to -20c 500 mb temperatures is
contributing to 500-750 J/kg of MLCAPE across much of central
Nevada. Favorable veering wind profiles to the east of the low
center with deep-layer shear around 40 kts should be sufficient for
a few organized storms, including supercells. The steep lapse rates
in the mid-levels will promote hail growth within the strongest
storms as well as the potential for damaging wind gusts through this
evening. Trends will be monitored but a watch is not expected at
this time.

..Lyons/Guyer.. 05/15/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...VEF...LKN...REV...

LAT...LON   39131891 40511881 41201808 41521685 41201555 40471500
            39191545 38541660 38161721 38211791 38341815 39131891

Nearby

Mesoscale Discussions in Nevada, 2021 Every mesoscale discussion in 2021

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.