Alert archive / Arizona / Severe Thunderstorm Warnings in 1998

Severe Thunderstorm Warning 49, NWS Tucson, AZ

August 5, 1998Pima County, Arizona

NWS Tucson, AZ issued this severe thunderstorm warning at Aug 5, 1998, 5:43 PM MST for Pima County, Arizona. It was in force for 62 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Aug 5, 1998, 5:43 PM MST (00:43 UTC)
Expired
Aug 5, 1998, 6:45 PM MST
In force
62 min
Issued by
NWS Tucson, AZ
Area
Whole counties

County Pima County, AZ

The radar

The Tucson radar (KEMX), 112 km from the middle of the area, began a volume at 00:46 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
Aug 5, 5:45 PM MSTHail 1Tucson, AZ

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Tuscon, AZ (KTUS), launched 00:00Z, 0.7 hours before the alert went out and 84 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, Tuscon, AZ at 00:00Z on 1998-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.1000850700500300200100-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Tuscon, AZ at 00:00Z on 1998-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 square meters per square second.193958Sfc1 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
7202 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
97 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.

447 
WUUS1 KTUS 060044 RRA
SVRTUS
AZC019-060145-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TUCSON AZ
543 PM MST WED AUG 5 1998

THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN PIMA COUNTY IN SOUTHERN ARIZONA
  INCLUDING THE TUCSON METRO AREA...

* UNTIL 645 PM MST

* AT 544 PM MST... DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM IN
  THE VICINITY OF NORTHEAST TUCSON MOVING SOUTHWEST AT 15 MPH.

VPH

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tucson, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 5, 2:30 PM MST, 3 hours 13 minutes earlier.

Area forecast discussion, Aug 5, 2:30 PM MST, 3 hours 13 minutes before
SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
230 PM MST WED AUG 5 1998

SYNOPSIS...A SURGE ON MOISTURE FROM THE GULF OF CALIFORNIA HAS
MOVED INTO SOUTHERN ARIZONA THIS MORNING. NORTHERLY FLOW ALOFT WILL
BECOME EASTERLY BY FRIDAY FOR AN UPSWING IN THUNDERSTORM ACTIVITY
THROUGH THE END OF THE WORK WEEK.

DISCUSSION...GULF SURGE FROM THIS MORNING HAS WEAKENED AT YUMA BUT
SURFACE DEWPOINT VALUES HAVE NOT MIXED OUT AND REMAIN IN THE UPPER
50S TO LOWER 60S. WATER VAPOR PICTURE SHOWS THIS WEDGE OF MID-LVL
MOISTURE ACROSS THE WHITE MOUNTAINS. THIS AREA WAS THE FIRST TO
START WITH CONVECTION EARLIER THIS AFTERNOON AND ANSWERED ONE OF MY
QUESTIONS FROM MORNING DISCUSSION. AS OF 2PM/21Z THE BIGGEST STORMS
WERE JUST SOUTH OF THE BORDER IN NORTHERN MEXICO WHERE THE MOISTURE
IS MUCH RICHER. MODELS PROG WEAK SHORT WAVE TO MOVE SOUTH TO DOUGLAS
TONIGHT AND WITH COOL POOL ALOFT (-10C AIR) MAY HELP INITIATE
CONVECTION TONIGHT. WILL PUT HIGHEST POPS EAST AND SOUTH OF TUCSON.

UPPER HIGH CURRENTLY NW OF LAS VEGAS WILL DRIFT EAST TOWARD THE FOUR
CORNERS REGION BY FRIDAY. UPPER WINDS WILL BECOME NELY THURSDAY THAN
EASTERLY ON FRIDAY. LOW-LEVEL MOISTURE INTRUSION WILL CONTINUE WITH
TODAY ONLY SETTING CONDITIONS UP. CONCERN FOR THURSDAY IS POSSIBLE
SEVERE WEATHER EVENT WITH LAPSE RATES CONTINUING RATHER STEEP FOR
POSSIBLE MICROBURST ACTIVITY. SPC (STORMS PREDICTION CENTER) ALREADY
HAS PORTIONS OF SE AZ IN SLIGHT RISK CATEGORY. WILL HIGHLIGHT STRONG
WINDS IN AFTERNOON ZONE PACKAGE. TUS 2343. GLUECK

.TWC...NONE.

In the hours before

Special weather statement, Aug 5, 12:45 PM MST, 4 hours 58 minutes before
AZZ019-029>035-060700-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1245 PM MST WED AUG 5 1998...THIS PRODUCT IS NOT UPDATED

                        *CONDITIONAL*    *CONDITIONAL*
                AREAL    PROBABILITY   RAIN GREATER THAN   STORM
COUNTY        COVERAGE    OF SEVERE     1.00       2.00    MOTION

COCHISE          30          15          30         10      S 12
GRAHAM           30          15          20          5      S 12
GREENLEE         30          15          20          0      S 12
TUCSON/ERN PIMA  20          15          30          0      S 10
TOHONO OODHAM   10          10          20          0      S 10
WESTERN PIMA      0           0           0          0
SOUTHEAST PINAL  10          10          20          0      S 10
SANTA CRUZ       30          15          30         10      S 12

SYNOPSIS...SURFACE DEWPOINT VALUES HAVE INCREASED ALL OVER SOUTHEAST
ARIZONA THIS MORNING IN RESPONSE TO SUGRE OF MOISTURE FROM THE GULF
OF CALIFORNIA. A WEATHER DISTURBANCE WILL MOVE SOUTH FROM NORTHEAST
ARIZONA OVER SOUTHEAST ARIZONA LATER TODAY INTO TONIGHT. THE BEST
THREAT OF THUNDERSTORMS WILL BE SOUTH AND EAST OF TUCSON WITH LOCAL
RAINFALL TOTALS NEAR 3/4 OF AN INCH.
*****************************************************************
KEY...
AREAL COVERAGE - PERCENT OF COUNTY OR AREA THAT WILL EXPERIENCE
                  THUNDERSTORMS
PROB OF SEVERE - THE PROBABILITY THAT ANY ONE OF THE STORMS WILL
                  REACH SEVERE LEVELS (DAMAGING WIND AND/OR
                  LARGE HAIL)
RAIN GRTR THAN - THE PROBABILITY THAT ANY ONE OF THE STORMS WILL
                  PRODUCE RAIN EXCEEDING 1 INCH OR 2 INCHES IN
                  ANY LOCATION
STORM MOTION   - GENERAL DIRECTION TO WHICH THE STORMS WILL
                  LIKELY MOVE AND SPEED IN MPH

NOTE...
VALID TIME IS FROM 12:45 PM TO 12 MIDNIGHT OF THE DAY OF ISSUANCE.
THIS PRODUCT IS NOT TO BE USED IN PLACE OF SEVERE THUNDERSTORM OR
FLASH FLOOD WARNINGS OR WATCHES. THIS PRODUCT IS ONLY USED FOR
OUTLOOK PURPOSES. CORRESPONDING GRAPHICS MAY BE FOUND ON THE NWS
TUCSON INTERNET PAGE AT
HTTP://NIMBO.WRH.NOAA.GOV/TUCSON/SWO/SWO.SHTML

END/RO
Special weather statement, Aug 5, 12:45 PM MST, 4 hours 58 minutes before
AZZ019-029>035-060700-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1245 PM MST WED AUG 5 1998...THIS PRODUCT IS NOT UPDATED

                        *CONDITIONAL*    *CONDITIONAL*
                AREAL    PROBABILITY   RAIN GREATER THAN   STORM
COUNTY        COVERAGE    OF SEVERE     1.00       2.00    MOTION

COCHISE          30          15          30         10      S 12
GRAHAM           30          15          20          5      S 12
GREENLEE         30          15          20          0      S 12
TUCSON/ERN PIMA  20          15          30          0      S 10
TOHONO OODHAM   10          10          20          0      S 10
WESTERN PIMA      0           0           0          0
SOUTHEAST PINAL  10          10          20          0      S 10
SANTA CRUZ       30          15          30         10      S 12

SYNOPSIS...SURFACE DEWPOINT VALUES HAVE INCREASED ALL OVER SOUTHEAST
ARIZONA THIS MORNING IN RESPONSE TO SUGRE OF MOISTURE FROM THE GULF
OF CALIFORNIA. A WEATHER DISTURBANCE WILL MOVE SOUTH FROM NORTHEAST
ARIZONA OVER SOUTHEAST ARIZONA LATER TODAY INTO TONIGHT. THE BEST
THREAT OF THUNDERSTORMS WILL BE SOUTH AND EAST OF TUCSON WITH LOCAL
RAINFALL TOTALS NEAR 3/4 OF AN INCH.
*****************************************************************
KEY...
AREAL COVERAGE - PERCENT OF COUNTY OR AREA THAT WILL EXPERIENCE
                  THUNDERSTORMS
PROB OF SEVERE - THE PROBABILITY THAT ANY ONE OF THE STORMS WILL
                  REACH SEVERE LEVELS (DAMAGING WIND AND/OR
                  LARGE HAIL)
RAIN GRTR THAN - THE PROBABILITY THAT ANY ONE OF THE STORMS WILL
                  PRODUCE RAIN EXCEEDING 1 INCH OR 2 INCHES IN
                  ANY LOCATION
STORM MOTION   - GENERAL DIRECTION TO WHICH THE STORMS WILL
                  LIKELY MOVE AND SPEED IN MPH

NOTE...
VALID TIME IS FROM 12:45 PM TO 12 MIDNIGHT OF THE DAY OF ISSUANCE.
THIS PRODUCT IS NOT TO BE USED IN PLACE OF SEVERE THUNDERSTORM OR
FLASH FLOOD WARNINGS OR WATCHES. THIS PRODUCT IS ONLY USED FOR
OUTLOOK PURPOSES. CORRESPONDING GRAPHICS MAY BE FOUND ON THE NWS
TUCSON INTERNET PAGE AT
HTTP://NIMBO.WRH.NOAA.GOV/TUCSON/SWO/SWO.SHTML

END/RO

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 5:24 PM MSTFlash Flood WarningTWCPima2 hr
Aug 5, 6:38 PM MSTFlash Flood WarningTWCPima52 min
Aug 5, 6:38 PM MSTSevere Thunderstorm WarningTWCPima52 min
Aug 5, 7:20 PM MSTSevere Thunderstorm WarningTWCPima, Santa Cruz75 min
Aug 5, 8:54 PM MSTFlash Flood WarningTWCPima96 min
Aug 5, 11:56 PM MSTSevere Thunderstorm WarningTWCPinal49 min
Aug 6, 2:44 AM MSTSevere Thunderstorm WarningTWCPima61 min

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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.