Tornadoes · United States · Arkansas · 1999

F2 tornado, Grannis to Glenwood, Arkansas, March 5, 1999

From Grannis to Glenwood, this F2 tornado ran 27.2 miles across Polk, Howard and Pike counties on March 5, 1999, touching down at 6:18 PM CST and reaching 183 yards wide. It killed nobody, and did $60,000 of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. F040 to 72 mph

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. F173 to 112 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. F2113 to 157 mphthis tornado

    Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

  4. F3158 to 206 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. F4207 to 260 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. F5261 to 318 mph

    Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

  7. Unrated

    The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

The record

Rating
F2
Date
March 5, 1999
Touchdown
6:18 PM CST (00:18 UTC)
Path length
27.2 miles (43.8 km)
Path width
183 yards (167 m)
Deaths
0
Injuries
0
Property damage
$60,000
Counties
Polk, Howard and Pike counties
Touchdown point
34.200, -94.370
Lift-off point
34.250, -93.900
Record number
167

What the Weather Service recorded

A strong tornado was spawned in southern Polk County. The tornado hit the town of Grannis and caused some property damage. Damage was most extensive at a chicken farm. Two chicken houses were completely destroyed at the farm, with one chicken house thrown into the other house. Roughly 8,000 chickens were lost. Several trees and a few power lines were downed as well. The tornado tracked about 8 miles before moving into Howard County (Shreveport County Warning Area).

A strong tornado was spawned in eastern Pike County. The tornado moved through mostly rural areas, so property damage was minimal. However, numerous trees were downed. The tornado was on the ground for around 10 miles before moving into western Clark County.

Tornado entered Howard County from Polk County, moved across Howard County, then into Pike County. Damage was largely confined to rural wooded area with little or no population. A mobile home was heavily damaged and scores of trees were toppled along the tornado path.

A strong tornado moved out of Howard County (Shreveport County Warning Area) into western Pike County. The tornado was weakening, but still heavily damaged a trailer and knocked down a few trees. The tornado tracked only half a mile into Pike County before dissipating.

A strong tornado was spawned south of a dissipating tornado in western Pike County. The former tornado tracked mostly through rural areas and caused little in the way of property damage. However, tree damage was extensive...especially just to the southeast of Newhope. The tornado tracked about 10 miles before dissipating.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

The warnings

42 minutes of warning. NWS LZK issued a tornado warning for this county at 23:36 UTC, 42 minutes before the tornado touched down, in force until 00:25 UTC.

Issued (UTC)ExpiredProductOffice
23:02 UTC00:05 UTCSevere Thunderstorm WarningLZK
23:36 UTC00:25 UTCTornado WarningLZK
00:02 UTC01:05 UTCSevere Thunderstorm WarningLZK

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The forecast that day

The Storm Prediction Center had this point in a Slight Risk. The outlook in force was issued at 19:46 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The air that afternoon

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Shreveport, LA (KSHV), 00:00Z

0.3 hours before the tornado, 197 km from the path. March 6, 1999.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 00:00Z on 1999-03-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 859 joules per kilogram, CIN -20, lifted condensation level 753 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Shreveport, LA at 00:00Z on 1999-03-06The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 158 square meters per square second, 0 to 6 km bulk shear 43 knots.1939587897117136Sfc1 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. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
859 J/kg
Mixed-layer CIN
-20 J/kg
Surface CAPE
1280 J/kg
Mixed-layer LCL
753 m above ground
0-6 km bulk shear
43 kt
0-1 km bulk shear
19 kt
0-1 km storm-relative helicity
158 m²/s²
0-3 km storm-relative helicity
259 m²/s²
Significant tornado parameter
1.2
Supercell composite
7.9
0-3 km lapse rate
6.5 K/km

Open this sounding in Storm Lab

Shreveport, LA (KSHV), 12:00Z

11.7 hours after it, 197 km from the path. March 6, 1999.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 12:00Z on 1999-03-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -45618, lifted condensation level 1701 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Shreveport, LA at 12:00Z on 1999-03-06The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity -47 square meters per square second, 0 to 6 km bulk shear 49 knots.1939587897Sfc1 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. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
-45618 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1701 m above ground
0-6 km bulk shear
49 kt
0-1 km bulk shear
11 kt
0-1 km storm-relative helicity
-47 m²/s²
0-3 km storm-relative helicity
-54 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
2.5 K/km

Open this sounding in Storm Lab

The surface observations

Mount Ida (MWT), 62 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
22:22 UTC66.259 4 kt1007.1
22:53 UTC6859180° 9 kt181007.1
23:29 UTC66.259180° 8 kt171006.8
23:37 UTC66.259170° 8 kt151006.8
23:53 UTC6759170° 9 kt141007.1
00:39 UTC64.460.8 5 kt1006.8+RA BR
00:53 UTC6356210° 13 kt271006.8+RA
00:58 UTC62.655.4290° 7 kt231007.8RA
01:08 UTC62.655.4210° 12 kt191007.1-RA

From the Iowa Environmental Mesonet's archive of airport observations.

This ground now

The live radar over the trackEvery 1999 tornado in ArkansasEvery tornado in Arkansas since 1950Warnings in force in Arkansas nowThe forecast where you are

The other tornadoes of March 5, 1999

11 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
March 54:36 PM CSTF0Crawford, AR0.530$1,000
March 55:30 PM CSTF2Johnson, AR7.0200
March 55:42 PM CSTF2Polk, AR12.0200
March 55:46 PM CSTF1Johnson, AR7.0100
March 56:15 PM CSTF1Pope, AR10.0100
March 56:55 PM CSTF1Van Buren, AR5.5100
March 56:56 PM CSTF2Pike, AR10.0200
March 57:02 PM CSTF3Van Buren, AR10.0350
March 57:16 PM CSTF3Pike, AR13.0400$2.0 million
March 57:43 PM CSTF2Clark, AR23.0200
March 58:34 PM CSTF1Hot Spring, AR12.0100

What this means

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

Sources

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.