Alert archive / Arizona / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 21, NWS Flagstaff, AZ

July 21, 1998Navajo County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 21, 1998, 7:15 PM MDT for Navajo County, Arizona. It was in force for 50 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 21, 1998, 7:15 PM MDT (01:15 UTC)
Expired
Jul 21, 1998, 8:05 PM MDT
In force
50 min
Issued by
NWS Flagstaff, AZ
Area
Whole counties

County Navajo County, AZ

The radar

The Flagstaff radar (KFSX), 122 km from the middle of the area, began a volume at 01:16 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

Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 1.3 hours before the alert went out and 136 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, Flgstf/Belemont, AZ at 00:00Z on 1998-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 169 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 00:00Z on 1998-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 6 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
169 J/kg
Mixed-layer CIN
-65 J/kg
Mixed-layer LCL
1458 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
6 m²/s²
0-3 km storm-relative helicity
20 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

626 
WUUS1 KFLG 220118 RRA
SVRFLG
AZC017-220205-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
615 PM MST TUE JUL 21 1998

THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL NAVAJO COUNTY IN NORTHEASTERN ARIZONA

* UNTIL 705 PM MST

* AT 615 PM MST...  NATIONAL WEATHER SERVICE DOPPLER RADAR
  INDICATED A SEVERE THUNDERSTORM 29 MILES EAST OF WINSLOW OR 12
  MILES NORTHEAST OF JOSEPH CITY MOVING WEST AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  JOSEPH CITY AT 635 PM MST

IF YOU ARE IN THE WARNING AREA... SEEK SAFETY IN AN INTERIOR ROOM
AWAY FROM WINDOWS. IF YOU ARE CAUGHT OUTSIDE... TRY TO FIND
SHELTER IN A WELL PROTECTED AREA. SEVERE THUNDERSTORMS PRODUCE
DAMAGING WIND AND HAIL ALONG WITH VERY HEAVY RAIN AND FREQUENT
LIGHTNING.

The office that day

Everything else NWS Flagstaff, AZ issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 21, 6:28 PM MDTSevere Thunderstorm WarningFGZNavajo47 min
Jul 21, 8:05 PM MDTSevere Thunderstorm WarningFGZNavajo30 min
Jul 22, 12:55 PM MDTSevere Thunderstorm WarningFGZCoconino50 min
Jul 22, 1:25 PM MDTFlash Flood WarningFGZCoconino115 min
Jul 22, 1:54 PM MDTFlash Flood WarningFGZCoconino2 hr
Jul 22, 2:32 PM MDTFlash Flood WarningFGZCoconino2 hr
Jul 22, 4:50 PM MDTFlash Flood WarningFGZCoconino, Yavapai2 hr

Nearby

Severe Thunderstorm Warnings in Arizona, 1998Every severe thunderstorm warning in 1998

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.