Alert archive / Arizona / Severe Thunderstorm Warnings in 2001
Severe Thunderstorm Warning 54, NWS Flagstaff, AZ
NWS Flagstaff, AZ issued this severe thunderstorm warning at Aug 9, 2001, 1:37 PM MST for Coconino County, Yavapai County, Arizona. It was in force for 33 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 9, 2001, 1:37 PM MST (20:37 UTC)
- Expired
- Aug 9, 2001, 2:10 PM MST
- In force
- 33 min
- Issued by
- NWS Flagstaff, AZ
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Coconino County, AZ, Yavapai County, AZ
The radar
The Flagstaff radar (KFSX), 113 km from the middle of the area, began a volume at 20:38 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 |
|---|---|---|---|
| Aug 9, 1:45 PM MST | Hail 0.75 | Flagstaff, 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
Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 8.6 hours before the alert went out and 33 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
- 1 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1316 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 100 m²/s²
- 0-3 km storm-relative helicity
- 138 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 Flagstaff, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 9, 9:00 AM MST, 4 hours 37 minutes earlier.
Area forecast discussion, Aug 9, 9:00 AM MST, 4 hours 37 minutes before
NORTHERN ARIZONA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FLAGSTAFF AZ 900 AM MST THU AUG 09 2001 .SYNOPSIS...A LOW PRESSURE SYSTEM OVER NEW MEXICO WILL CONTINUE TO PRODUCE A MOIST NORTHEASTERLY FLOW OVER ARIZONA. THIS SYSTEM WILL BE RESPONSIBLE FOR CLOUDY...WET AND COOL WEATHER OVER MUCH OF THE STATE TODAY. THE LOW WILL BEGIN TO WEAKEN ON FRIDAY ALLOWING FOR A LITTLE DRIER AND WARMER WEATHER ON FRIDAY AND SATURDAY. THERE WILL BE ENOUGH MOISTURE INTO EARLY NEXT WEEK FOR A CHANCE OF AFTERNOON THUNDERSTORMS. .DISCUSSION...A MID TO UPPER TROUGH REMAINS OVER NEW MEXICO WITH AN AN UPPER RIDGE CENTERED OVER NORTHERN BAJA CALIFORNIA. AS A RESULT...A MOIST NORTHEAST FLOW WILL CONTINUE FOR THE NEXT 24-HOURS WITH SHOWERS AND THUNDERSTORMS POSSIBLE ALMOST ANY HOUR OF THE DAY (OF COURSE MOST NUMEROUS DURING THE AFTERNOON AND EVENING HOURS). LOOKS LIKE STORMS WILL BE MOST NUMEROUS TODAY OVER THE EASTERN MOGOLLON RIM...WHITE MOUNTAINS AND EASTERN LITTLE COLORADO RIVER VALLEY WHERE IT IS MOSTLY SUNNY THIS MORNING AND DEEP MOISTURE IS LOCATED. ELSEWHERE...IT REMAINS UNSTABLE ENOUGH FOR SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP TODAY WHERE BREAKS IN THE MID LEVEL CLOUD DECK FORM. FOR TONIGHT...WITH SUNNY SKIES OVER UTAH THIS MORNING...EXPECT ANOTHER ORGANIZED AREA OF THUNDERSTORMS TO MOVE INTO NORTH CENTRAL AND NORTHWEST PORTIONS OF ARIZONA DURING THE EVENING HOURS. ON FRIDAY...MODELS ARE INSISTING THAT THE UPPER RIDGE WILL SHIFT NORTHWARD WITH A DRIER NORTH TO NORTHWEST FLOW DEVELOPING. THINK THE NET RESULT WILL BE A SLIGHT DOWNTURN IN ACTIVITY AND A MORE DIURNAL NATURE TO THUNDERSTORMS. CURRENT FORECAST HANDLES THIS WELL. MCCOLLUM .FGZ...NONE.
In the hours before
Special weather statement, Aug 9, 9:30 AM MST, 4 hours 7 minutes before
AZZ004>018-037>040-091930- HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE FLAGSTAFF AZ 930 AM MST THU AUG 9 2001 ...SCATTERED THUNDERSTORMS TODAY ACROSS NORTHERN ARIZONA WITH THE POTENTIAL FOR HEAVY RAINFALL... A NEARLY STATIONARY UPPER LEVEL WEATHER DISTURBANCE OVER NEW MEXICO WILL CONTINUE TO PRODUCE A MOIST NORTHEAST FLOW ACROSS NORTHERN ARIZONA TODAY. WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED. THE MAIN THREAT FROM THESE STORMS WILL BE HEAVY RAIN...WITH RAINFALL AMOUNTS OF 1 TO 3 INCHES POSSIBLE...AND THE POTENTIAL FOR LOCALIZED FLASH FLOODING. FOR TODAY THE MOST INTENSE STORMS ARE EXPECTED OVER THE LITTLE COLORADO RIVER VALLEY...THE WHITE MOUNTAINS AND THE MOGOLLON RIM. FOR LATE THIS AFTERNOON AND EVENING STRONGER STORMS SHOULD MOVE INTO THE AREA OF THE KAIBAB PLATEAU...PAGE...THE GRAND CANYON AND THE COCONINO PLATEAU.
The office that day
Everything else NWS Flagstaff, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 9, 12:36 PM MST | Severe Thunderstorm Warning | FGZ | Coconino | 29 min |
| Aug 9, 2:45 PM MST | Flash Flood Warning | FGZ | Yavapai | 2 hr |
| Aug 9, 3:44 PM MST | Flash Flood Warning | FGZ | Yavapai | 2 hr |
Nearby
Severe Thunderstorm Warnings in Arizona, 2001Every severe thunderstorm warning in 2001
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.