Alert archive / Nevada / Areal Flood Advisories in 2021

Areal Flood Advisory 21, NWS Reno, NV

July 30, 2021Douglas County, Nevada

NWS Reno, NV issued this areal flood advisory at Jul 30, 2021, 4:55 PM PDT for Douglas County, Nevada. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Jul 30, 2021, 4:55 PM PDT (23:55 UTC)
Expired
Jul 30, 2021, 7:54 PM PDT
In force
3 hr
Issued by
NWS Reno, NV
Area
Storm-based polygon

County Douglas County, NV

The radar

The Reno radar (KRGX), 96 km from the middle of the area, began a volume at 23:55 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, 11.9 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.

Skew-T log-pSkew-T log-p diagram, Reno, NV at 12:00Z on 2021-07-30Temperature 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 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Reno, NV at 12:00Z on 2021-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 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
2579 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

979 
WGUS85 KREV 302355
FLSREV

Flood Advisory
National Weather Service Reno NV
455 PM PDT Fri Jul 30 2021

NVC005-310300-
/O.NEW.KREV.FA.Y.0021.210730T2355Z-210731T0300Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Douglas NV-
455 PM PDT Fri Jul 30 2021

The National Weather Service in Reno has issued a

* Urban and Small Stream Flood Advisory for...
  Douglas County in western Nevada...

* Until 800 PM PDT.

* At 455 PM PDT, Doppler radar indicated heavy rain due to 
  thunderstorms. This may result in urban and small stream flooding.

* Some locations that will experience flooding include...
  Mount Siegel.
  Pinenut Creek Watershed

PRECAUTIONARY/PREPAREDNESS ACTIONS...

In hilly terrain there are hundreds of low water crossings which are 
potentially dangerous in heavy rain. Do not attempt to cross flooded 
roads. Find an alternate route.

Move away from recently burned areas. Life-threatening flooding of 
creeks, roads, and normally dry stream beds is likely. The heavy 
rains will likely trigger rockslides, mudslides and debris flows in 
steep terrain, especially in and around these areas.

&&

LAT...LON 3889 11962 3890 11962 3891 11960 3891 11958
      3891 11956 3890 11951 3889 11950 3888 11953
      3889 11955 3889 11957 3887 11959 3888 11960
      3889 11960

$$

EW
1 follow-up statement
537 
WGUS85 KREV 310254
FLSREV

Flood Advisory
National Weather Service Reno NV
754 PM PDT Fri Jul 30 2021

NVC005-310304-
/O.CAN.KREV.FA.Y.0021.000000T0000Z-210731T0300Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Douglas NV-
754 PM PDT Fri Jul 30 2021

...THE URBAN AND SMALL STREAM FLOOD ADVISORY FOR DOUGLAS COUNTY HAS 
BEEN REPLACED WITH A FLASH FLOOD WARNING...

The heavy rain has ended. However, minor debris flows may be 
ongoing. It is best to stay away from the Numbers fire burn scar. 
Any additional rainfall this evening could cause further issues for 
the burn area. 

LAT...LON 3889 11962 3890 11962 3891 11960 3891 11958
      3891 11956 3890 11951 3889 11950 3888 11953
      3889 11955 3889 11957 3887 11959 3888 11960
      3889 11960

$$

EW

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 1:10 PM PDTSpecial Weather StatementREVChurchill, Douglas, Lyon, Mineral, Pershing, Storey and 1 more80 min

Nearby

Areal Flood Advisories in Nevada, 2021Every areal flood advisory 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.