Alert archive / Nevada / Flash Flood Watches in 2015

Flash Flood Watch 7, NWS Reno, NV

July 21, 20155 counties in Nevada; 5 counties in California

NWS Reno, NV issued this flash flood watch at Jul 21, 2015, 6:16 AM PDT for 5 counties in Nevada; 5 counties in California. It took effect at Jul 21, 2015, 12:00 PM PDT. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued: Jul 21, 2015, 6:16 AM PDT (13:16 UTC)
In effect from: Jul 21, 2015, 12:00 PM PDT
Expired: Jul 21, 2015, 6:17 PM PDT
In force: 6 hr
Issued by: NWS Reno, NV
Flood severity: None

Counties Alpine County, CA, El Dorado County, CA, Mono County, CA, Nevada County, CA, Placer County, CA, Douglas County, NV, Lyon County, NV, Mineral County, NV, Storey County, NV, Washoe County, NV

The radar

The Reno radar (KRGX), 84 km from the middle of the area, began a volume at 13:19 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

Reno, NV (KREV), launched 12:00Z, 1.3 hours before the alert went out and 144 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: 170 J/kg
Mixed-layer CIN: -146 J/kg
Mixed-layer LCL: 1898 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: 23 m²/s²
0-3 km storm-relative helicity: 138 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Reno, NV wrote its last area forecast discussion before this flash flood watch went out at Jul 21, 2:40 AM PDT, 3 hours 36 minutes earlier.

Area forecast discussion, Jul 21, 2:40 AM PDT, 3 hours 36 minutes before

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The office that day

Everything else NWS Reno, NV issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 21, 11:19 AM PDT	Special Weather Statement	REV	Douglas	56 min
Jul 21, 11:57 AM PDT	Special Weather Statement	REV		48 min
Jul 21, 12:51 PM PDT	Severe Thunderstorm Warning	REV	Douglas	39 min
Jul 21, 1:18 PM PDT	Special Weather Statement	REV	Storey	42 min
Jul 21, 1:37 PM PDT	Flash Flood Warning	REV	Washoe	3 hr
Jul 21, 2:34 PM PDT	Special Weather Statement	REV	Storey	26 min
Jul 21, 2:40 PM PDT	Special Weather Statement	REV		35 min
Jul 21, 3:04 PM PDT	Special Weather Statement	REV	Storey	26 min
Jul 21, 3:30 PM PDT	Special Weather Statement	REV		60 min
Jul 21, 4:05 PM PDT	Special Weather Statement	REV		40 min
Jul 21, 12:31 PM PDT	Special Weather Statement	REV	Sierra	44 min
Jul 21, 1:02 PM PDT	Areal Flood Advisory	REV	Sierra	118 min
Jul 21, 1:03 PM PDT	Special Weather Statement	REV	Lassen	57 min
Jul 21, 1:12 PM PDT	Severe Thunderstorm Warning	REV	Nevada, Placer	48 min
Jul 21, 1:42 PM PDT	Flash Flood Warning	REV	Nevada, Placer, Sierra	3 hr
Jul 21, 1:50 PM PDT	Special Weather Statement	REV	Sierra	40 min
Jul 21, 1:58 PM PDT	Severe Thunderstorm Warning	REV	Nevada, Placer	47 min
Jul 21, 2:16 PM PDT	Flash Flood Warning	REV	Nevada, Sierra	3 hr
Jul 21, 2:54 PM PDT	Special Weather Statement	REV	Lassen	36 min
Jul 21, 3:02 PM PDT	Severe Thunderstorm Warning	REV	Plumas	28 min
Jul 21, 3:21 PM PDT	Areal Flood Advisory	REV	Plumas	3 hr
Jul 21, 3:36 PM PDT	Severe Thunderstorm Warning	REV	Lassen, Plumas	54 min
Jul 21, 3:46 PM PDT	Severe Thunderstorm Warning	REV	El Dorado, Placer	44 min
Jul 21, 4:43 PM PDT	Special Weather Statement	REV	Lassen	47 min

Nearby

Flash Flood Watches in Nevada, 2015 Flash Flood Watches in California, 2015 Every flash flood watch in 2015

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.