Alert archive / Utah / Flash Flood Warnings in 2018

Flash Flood Warning 21, NWS Salt Lake City, UT

July 14, 2018Iron County, Kane County, Washington County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jul 14, 2018, 4:32 PM MDT for Iron County, Kane County, Washington County, Utah. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 14, 2018, 4:32 PM MDT (22:32 UTC)
Expired
Jul 14, 2018, 7:30 PM MDT
In force
3 hr
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Flood severity
None

Counties Iron County, UT, Kane County, UT, Washington County, UT

The radar

The Cedar City radar (KICX), 29 km from the middle of the area, began a volume at 22:32 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

Las Vegas, NV (KVEF), launched 12:00Z, 10.5 hours before the alert went out and 253 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, Las Vegas, NV at 12:00Z on 2018-07-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 267 joules per kilogram.LCLLFCEL10008507005003002001001 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, Las Vegas, NV at 12:00Z on 2018-07-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 square meters per square second.1939Sfc1 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
267 J/kg
Mixed-layer CIN
-186 J/kg
Mixed-layer LCL
2240 m above ground
0-6 km bulk shear
5 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
-28 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

403 
WGUS55 KSLC 142232
FFWSLC
UTC021-025-053-150130-
/O.NEW.KSLC.FF.W.0021.180714T2232Z-180715T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
432 PM MDT SAT JUL 14 2018

The National Weather Service in Salt Lake City has issued a

* Flash Flood Warning for...
  East central Washington County in southwestern Utah...
  Western Kane County in southern Utah...
  South central Iron County in southern Utah...

* Until 730 PM MDT
    
* At 429 PM MDT, Doppler radar indicated a thunderstorm producing 
  heavy rain over portions over the North Fork of the Virgin River 
  and the Narrows in Zion National Park as well as Oak Creek, 
  Crystal Creek, and Deep Creek. Up to one inch of rain has already 
  fallen. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Telephone Canyon
  Pine Creek Slot Canyon
  Clear Creek Slot Canyon
  Key Hole Canyon
  Spry Canyon
  Lodge Canyon 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 3751 11290 3713 11290 3715 11305 3729 11297
      3734 11303 3751 11303

$$

MT
2 follow-up statements
525 
WGUS75 KSLC 150009
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
609 PM MDT SAT JUL 14 2018

UTC021-025-053-150130-
/O.CON.KSLC.FF.W.0021.000000T0000Z-180715T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Washington UT-Kane UT-Iron UT-
609 PM MDT SAT JUL 14 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 730 PM MDT FOR
EAST CENTRAL WASHINGTON...WESTERN KANE AND SOUTH CENTRAL IRON
COUNTIES...

At 607 PM MDT, heavy rain has moved out of Zion National Park but 
flooding is still possible from earlier flooding that impacted the 
North Fork of the Virgin River and the Narrows. 

Some locations that will experience flooding include...
Telephone Canyon, Pine Creek Slot Canyon, Clear Creek Slot Canyon, 
Key Hole Canyon, Spry Canyon, and Lodge Canyon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

Please report flooding to your local law enforcement agency when you
can do so safely.

&&

LAT...LON 3751 11290 3713 11290 3715 11305 3729 11297
      3734 11303 3751 11303

$$

MT
971 
WGUS75 KSLC 150127
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
727 PM MDT SAT JUL 14 2018

UTC021-025-053-150136-
/O.EXP.KSLC.FF.W.0021.000000T0000Z-180715T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Washington UT-Kane UT-Iron UT-
727 PM MDT SAT JUL 14 2018

...THE FLASH FLOOD WARNING FOR EAST CENTRAL WASHINGTON...WESTERN KANE
AND SOUTH CENTRAL IRON COUNTIES WILL EXPIRE AT 730 PM MDT...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 3751 11290 3713 11290 3715 11305 3729 11297
      3734 11303 3751 11303

$$

MT

The office that day

Everything else NWS Salt Lake City, UT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 13, 7:37 PM MDTFlash Flood WarningSLCWashington3 hr
Jul 13, 10:44 PM MDTFlash Flood WarningSLCKane, San Juan2 hr
Jul 14, 12:41 PM MDTFlash Flood WarningSLCKane3 hr
Jul 14, 1:46 PM MDTFlash Flood WarningSLCKane3 hr
Jul 14, 3:02 PM MDTSpecial Weather StatementSLCWashington28 min
Jul 14, 3:23 PM MDTAreal Flood AdvisorySLCWashington97 min
Jul 14, 3:33 PM MDTFlash Flood WarningSLCGarfield, Kane4 hr
Jul 14, 4:16 PM MDTAreal Flood AdvisorySLCWashington89 min

Nearby

Flash Flood Warnings in Utah, 2018Every flash flood warning in 2018

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.