Alert archive / Arkansas / Flash Flood Warnings in 2018

Flash Flood Warning 13, NWS Shreveport, LA

February 21, 20184 counties in Arkansas

NWS Shreveport, LA issued this flash flood warning at Feb 21, 2018, 3:52 PM CST for 4 counties in Arkansas. It was in force for 113 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Feb 21, 2018, 3:52 PM CST (21:52 UTC)
Expired
Feb 21, 2018, 5:45 PM CST
In force
113 min
Issued by
NWS Shreveport, LA
Area
Storm-based polygon
Flood severity
None

Counties Hempstead County, AR, Howard County, AR, Little River County, AR, Sevier County, AR

The radar

The Shreveport radar (KSHV), 147 km from the middle of the area, began a volume at 21:51 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.

What was reported inside it

TimeReportWhereRemark
Feb 21, 5:30 PM CSTFLASH FLOOD7 Nw Patmos, ARHIGH WATER OVER ROAD REPORTED AT HEMPSTEAD 5 NEAR SPRINGHILL, AR.
Feb 21, 5:32 PM CSTFLASH FLOOD1 Nnw Perrytown, ARFLOODING REPORTED ON HEMPSTEAD 243.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Shreveport, LA (KBAD), launched 12:00Z, 9.9 hours before the alert went out and 145 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, Shreveport, LA at 12:00Z on 2018-02-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1043 joules per kilogram.LCLEL10008507005003002001001 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, Shreveport, LA at 12:00Z on 2018-02-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 151 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
1043 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
529 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
151 m²/s²
0-3 km storm-relative helicity
175 m²/s²
Significant tornado parameter
0.7
Supercell composite
4.1

Open this sounding in Storm Lab

The text

As transmitted.

458 
WGUS54 KSHV 212152
FFWSHV
ARC057-061-081-133-212345-
/O.NEW.KSHV.FF.W.0013.180221T2152Z-180221T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Shreveport LA
352 PM CST WED FEB 21 2018

The National Weather Service in Shreveport has issued a

* Flash Flood Warning for...
  Southeastern Little River County in southwestern Arkansas...
  Hempstead County in southwestern Arkansas...
  Eastern Sevier County in southwestern Arkansas...
  Howard County in southwestern Arkansas...

* Until 545 PM CST

* At 351 PM CST, Doppler radar indicated heavy rain across the 
  warned area. Three to four inches of rain have already fallen. 
  Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Hope, Ashdown, Nashville, Mineral Springs, Dierks, Umpire,
  Lockesburg, Emmet, Wilton, Blevins, Perrytown, Tollette, Fulton,
  Washington, Ogden, Ben Lomond, Corinth, Center Point, Saratoga and
  Athens.

Additional rainfall amounts of one to two are possible in the warned 
area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3435 9394 3419 9392 3418 9382 3401 9382
      3396 9346 3348 9349 3348 9372 3352 9375
      3350 9377 3361 9382 3358 9393 3355 9394
      3358 9397 3353 9399 3356 9400 3359 9418
      3356 9419 3356 9425 3435 9414

$$

19

The office that day

Everything else NWS Shreveport, LA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 21, 9:30 AM CSTAreal Flood AdvisorySHVHoward, Little River, Sevier3 hr
Feb 21, 9:57 AM CSTRiver Flood WarningSHVLittle River, Sevier6 days
Feb 21, 9:57 AM CSTRiver Flood WarningSHVHoward, Little River, Sevier7 days
Feb 21, 10:04 AM CSTRiver Flood WarningSHVLittle River5 days
Feb 21, 11:31 AM CSTFlash Flood WarningSHVColumbia, Hempstead, Howard, Lafayette, Little River, Miller and 2 more3 hr
Feb 21, 2:38 PM CSTFlash Flood WarningSHVColumbia, Nevada, Union16 hr

Nearby

Flash Flood Warnings in Arkansas, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.