Alert archive / Arizona / Tornado Warnings in 1999
Tornado Warning 4, NWS Flagstaff, AZ
NWS Flagstaff, AZ issued this tornado warning at Sep 15, 1999, 5:12 PM MST for Yavapai County, Arizona. It was in force for 33 min. 2 reports 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
- Sep 15, 1999, 5:12 PM MST (00:12 UTC)
- Expired
- Sep 15, 1999, 5:45 PM MST
- In force
- 33 min
- Issued by
- NWS Flagstaff, AZ
- Area
- Whole counties
County Yavapai County, AZ
The radar
The Flagstaff radar (KFSX), 124 km from the middle of the area, began a volume at 00:11 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Sep 15, 5:13 PM MST | Tornado F0 | Dewey, AZ | |
| Sep 15, 5:23 PM MST | Hail 1.75 | Dewey, AZ | For the second day in a row, vertical wind shear combined with monsoon moisture to produce several instances of severe weather. Hail did significant damage in Prescott Valley and in Dewey, with newspaper accounts indicate widespread damage to cars and skylight |
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
Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 0.2 hours before the alert went out and 98 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.
- Mixed-layer CAPE
- 419 J/kg
- Mixed-layer CIN
- -19 J/kg
- Mixed-layer LCL
- 1527 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 64 m²/s²
- 0-3 km storm-relative helicity
- 109 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.4
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KFLG 160013 RRA TORFLG AZC025-160045- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE FLAGSTAFF AZ 512 PM MST WED SEP 15 1999 THE NATIONAL WEATHER SERVICE IN FLAGSTAFF HAS ISSUED A * TORNADO WARNING FOR... CENTRAL YAVAPAI COUNTY IN CENTRAL ARIZONA * UNTIL 545 PM MST * AT 511 PM MST... DOPPLER RADAR AND SPOTTERS INDICATED A TORNADO 12 MILES EAST OF PRESCOTT OR 2 MILES NORTHWEST OF DEWEY... MOVING SOUTHEAST AT 10 MPH. * THIS TORNADIC STORM IS EXPECTED TO BE NEAR... DEWEY AT 520 PM MST A TORNADO IS ON THE GROUND! GO TO THE BASEMENT! IF A BASEMENT IS NOT AVAILABLE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR! JD
What forecasters said that day
The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Flagstaff, AZ wrote its last area forecast discussion before this tornado warning went out at Sep 15, 2:50 PM MST, 2 hours 22 minutes earlier.
Area forecast discussion, Sep 15, 2:50 PM MST, 2 hours 22 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION...CORRECTION TO SYNOPSIS NATIONAL WEATHER SERVICE FLAGSTAFF AZ 250 PM MST WED SEP 15 1999 SYNOPSIS...A WEAK TROUGH WILL CONTINUE MOVING ACROSS NORTHERN ARIZONA THROUGH TONIGHT. THUNDERSTORMS WILL BEGIN DISSIPATING LATER THIS EVENING IN THE WEST...WHILE CONTINUING PAST MIDNIGHT NEAR THE WHITE MOUNTAINS. LINGERING MOISTURE WILL ALLOW ISOLATED THUNDERSTORMS TO DEVELOP WEST OF THE RIM...WITH SCATTERED STORMS ALONG THE HIGHER TERRAIN OF THE RIM COUNTRY. A DRYING TREND WILL BEGIN ON FRIDAY...BUT SOME MOISTURE ALONG WITH A CHANCE OF THUNDERSTORMS WILL LINGER OVER EASTERN ARIZONA THROUGH MONDAY. DISCUSSION...FORECAST FOCUS REMAINS ON THE EFFECTS OF THE MID LEVEL SHORTWAVE THROUGH THE AREA. THUNDERSTORMS CONTINUE MOVING ALONG A LINE IN THE SOUTHERN TO SOUTHEASTERN CWA. STORMS ARE MOVING EAST WITH A SMALL GROUP COMPONENT TO THE NORTH. NONE OF THE STORMS HAVE GOTTEN OUT OF HAND YET. THE ACTIVITY SHOULD CONTINUE MOVING EAST THROUGH TONIGHT...WITH A DIURNAL TENDENCY TOWARD CLEARING. STORMS WILL CONTINUE UNTIL PRETTY LATE TONIGHT. FOG IS A POSSIBILITY AGAIN IN SOME OF THOSE AREAS THE REALLY CLEAR OUT. MOISTURE WILL BE SLOW TO CLEAR OUT WITH THE RIDGE SETTING UP OVER SOUTHERN NEW MEXICO THURSDAY. SCATTERED THUNDERSTORMS ARE LIKELY TO DEVELOP OVER THE ERN AND SRN PORTIONS OF THE CWA. WITH MORE OF A DIURNAL TENDENCY...WILL GO WITH SLIGHT CHANCE POPS THURDAY NIGHT WHILE EXPECTING STORMS TO END LATE. BY FRIDAY...RH IS HIGH ENOUGH OVER THE WHITE MTNS AND RIM COUNTRY FOR CHANCE POPS MENTIONED OVER THE HIGHER TERRAIN. IN THE EXTENDED...SATURDAY THROUGH MONDAY...MOISTURE APPEARS TO LINGER IN THE FLG CWA THROUGH SATURDAY...WITH A CHANCE OF PRECIP. SUNDAY AND MONDAY LOOK TO BE DRIER AS THE RIDGE AXIS PUSHES EAST. WILL KEEP A CHANCE OF PRECIP IN THE EASTERN ZONES THROUGH DAY 5. PEREZ .FLG...NONE.
In the hours before
Local storm report, Sep 15, 5:08 PM MST, 4 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
508 PM MST WED SEP 15 1999
TIME(MST) .....CITY LOCATION.....STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0455 PM PRESCOTT VALLEY AZ 2 INCH HAIL
09/15/99 YAVAPAI SKYLIGHT DAMAGE
JDLocal storm report, Sep 15, 5:08 PM MST, 4 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
508 PM MST WED SEP 15 1999
TIME(MST) .....CITY LOCATION.....STATE ...EVENT/REMARKS...
....COUNTY LOCATION....
0455 PM PRESCOTT VALLEY AZ 2 INCH HAIL
09/15/99 YAVAPAI SKYLIGHT DAMAGE
JDThe office that day
Everything else NWS Flagstaff, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 15, 5:42 PM MST | Severe Thunderstorm Warning | FGZ | Yavapai | 33 min |
| Sep 16, 11:15 AM MST | Severe Thunderstorm Warning | FGZ | Coconino | 30 min |
| Sep 16, 11:33 AM MST | Severe Thunderstorm Warning | FGZ | Coconino | 47 min |
| Sep 16, 12:19 PM MST | Severe Thunderstorm Warning | FGZ | Yavapai | 41 min |
| Sep 16, 12:35 PM MST | Severe Thunderstorm Warning | FGZ | Coconino | 45 min |
| Sep 16, 12:42 PM MST | Severe Thunderstorm Warning | FGZ | Coconino | 48 min |
| Sep 16, 1:17 PM MST | Tornado Warning | FGZ | Coconino | 33 min |
| Sep 16, 1:59 PM MST | Tornado Warning | FGZ | Coconino | 16 min |
| Sep 16, 2:24 PM MST | Tornado Warning | FGZ | Coconino | 11 min |
| Sep 16, 2:30 PM MST | Severe Thunderstorm Warning | FGZ | Navajo | 50 min |
| Sep 16, 2:54 PM MST | Severe Thunderstorm Warning | FGZ | Yavapai | 46 min |
| Sep 16, 4:16 PM MST | Severe Thunderstorm Warning | FGZ | Yavapai | 49 min |
Nearby
Tornado Warnings in Arizona, 1999Every tornado warning in 1999Tornadoes 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.