Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 508, NWS Tulsa, OK

September 10, 1999Pawnee County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at Sep 10, 1999, 7:33 PM CDT for Pawnee County, Oklahoma. It was in force for 42 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: Sep 10, 1999, 7:33 PM CDT (00:33 UTC)
Expired: Sep 10, 1999, 8:15 PM CDT
In force: 42 min
Issued by: NWS Tulsa, OK
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Pawnee County, OK

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Sep 10, 3:00 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Sep 10, 7:30 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 0.6 hours before the alert went out and 137 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 877 J/kg
Mixed-layer CIN: -16 J/kg
Mixed-layer LCL: 2184 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 73 m²/s²
0-3 km storm-relative helicity: 215 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 6.9

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Tulsa, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 10, 3:30 PM CDT, 4 hours 3 minutes earlier.

Area forecast discussion, Sep 10, 3:30 PM CDT, 4 hours 3 minutes before

EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
330 PM CDT FRI SEP 10 1999

PROBLEM(S) OF THE DAY:
WILL THE CONVECTION BE SCATTERED OR NUMEROUS?
HOW MUCH RAIN WILL FALL?

DESPITE MOVING INTO A DRIER AIR MASS...AREA OF THUNDERSTORMS THIS
MORNING PERSISTED AND REMAINED STRONG INTO THE AFTERNOON.  IT HAS
LEFT A WELL-DEFINED OUTFLOW BOUNDARY WHICH EXTENDS BACK INTO NORTH
CENTRAL OKLAHOMA.  MODELS INDICATE AN UPPER LEVEL DISTURBANCE MOVING
INTO WESTERN KANSAS WHICH WILL ACTIVATE A NEW ROUND OF STORMS WITHIN
THE WATCH AREA THIS EVENING.  WOULD GUESS THAT ACTIVITY IN WESTERN
PORTIONS OF WATCH AREA THIS EVENING WILL SPREAD INTO EASTERN OKLAHOMA
LATER TONIGHT.  IN THE MEANTIME...ATMOSPHERE OVER EASTERN PORTIONS OF
WATCH AREA WILL RE-DESTABILIZE LATER TONIGHT AS DEEPER LOW LEVEL
MOISTURE WILL INCREASE RAPIDLY TONIGHT.

AFTER THE ROUND OF THUNDERSTORMS OVERNIGHT...EXPECT A TEMPORARY BREAK
EARLY SATURDAY.  THEN IT MAY BE A MATTER OF FINDING THE BOUNDARIES
LEFT OVER FROM THE LATE NIGHT CONVECTION.  AFTER THAT...THE NEXT
PROBLEM WILL BE TIMING A STRONG COLD FRONT AS IT MOVES SOUTHEASTWARD
INTO FORECAST AREA.  LOOKS LIKE FRONT WILL ENTER INTO AREA DURING THE
DAY SUNDAY.  WILL BRING BACK A CHANCE OF THUNDERSTORMS LATE SATURDAY
NIGHT AND CONTINUE IT INTO SUNDAY.  ETA IS THE STRONGEST MODEL WITH
THE COLD FRONT AND WILL LEAN TOWARDS IT.

EXTENDED FORECAST LOOKS DRY AND COOL.

FCSTID = 11
TUL   65  88  67  85 /  50  30  20  40
FSM   63  90  67  87 /  30  40  30  30
MLC   65  90  66  87 /  30  40  30  30
BVO   63  87  65  84 /  60  30  20  40
FYV   60  86  62  84 /  30  40  20  30
BYV   60  86  62  84 /  30  40  20  30
MIO   63  87  65  84 /  60  30  20  40
MKO   65  88  67  85 /  50  30  20  40
F10   65  88  67  85 /  50  30  20  40
HHW   65  90  66  87 /  30  40  30  30

.TUL...
AR...NONE.
OK...SEVERE THUNDERSTORM WARNING UNTIL 342 PM CDT FridAy FOR ZONES
OKZ070...OKZ067...OKZ066.

SEVERE THUNDERSTORM WATCH UNTIL 900 PM CDT FridAy FOR ZONES
OKZ054>072...OKZ074...OKZ076.

--------------------
EXPERIMENTAL OUTPUT:

HAZARDOUS WEATHER EXPECTED NEXT 24 HOURS: GOOD CHANCE SEVERE
THUNDERSTORMS
NGM CONFIDENCE:  6 ON A SCALE OF 0 TO 10
ETA CONFIDENCE:  8 ON A SCALE OF 0 TO 10
AVN CONFIDENCE:  7 ON A SCALE OF 0 TO 10
FCST CONFIDENCE: 7 ON A SCALE OF 0 TO 10

In the hours before

Local storm report, Sep 10, 6:40 PM CDT, 53 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
640 PM CDT FRI SEP 10 1999

TIME(CDT)  .....CITY LOCATION..... STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0639 PM    3 S WELTY                 OK    1.75 INCH HAIL
09/10/99   OKFUSKEE

Local storm report, Sep 10, 6:52 PM CDT, 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
652 PM CDT FRI SEP 10 1999

TIME(CDT)  .....CITY LOCATION..... STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0620 PM    2 NE PADEN                OK    TORNADO
09/10/99   OKFUSKEE                        POSSIBLE
                                           TOUCHDOWN...SPOTTERS
                                           REPORTED TREES DOWN

Local storm report, Sep 10, 6:52 PM CDT, 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
652 PM CDT FRI SEP 10 1999

TIME(CDT)  .....CITY LOCATION..... STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0620 PM    2 NE PADEN                OK    TORNADO
09/10/99   OKFUSKEE                        POSSIBLE
                                           TOUCHDOWN...SPOTTERS
                                           REPORTED TREES DOWN

Local storm report, Sep 10, 7:09 PM CDT, 24 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
709 PM CDT FRI SEP 10 1999

TIME(CDT)  .....CITY LOCATION..... STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0707 PM    OKEMAH                    OK    1 INCH HAIL
09/10/99   OKFUSKEE

Local storm report, Sep 10, 7:25 PM CDT, 8 minutes before

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Local storm report, Sep 10, 7:25 PM CDT, 8 minutes before

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<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

Everything else NWS Tulsa, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 10, 7:13 PM CDT	Tornado Warning	TSA	Okfuskee	32 min
Sep 10, 8:12 PM CDT	Severe Thunderstorm Warning	TSA	Osage	48 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 1999 Every severe thunderstorm warning in 1999

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.