Alert archive / Arizona / Severe Thunderstorm Watches in 2014
Severe Thunderstorm Watch 508
The Storm Prediction Center issued this severe thunderstorm watch at Sep 27, 2014, 10:21 AM MST for 6 counties in Arizona; 4 counties in Utah. It was in force for 8 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 27, 2014, 10:21 AM MST (17:21 UTC)
- Expired
- Sep 27, 2014, 6:00 PM MST
- In force
- 8 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
Counties Coconino County, AZ, Gila County, AZ, Maricopa County, AZ, Navajo County, AZ, Pinal County, AZ, Yavapai County, AZ, Garfield County, UT, Kane County, UT, Piute County, UT, Wayne County, UT
The radar
The Flagstaff radar (KFSX), 60 km from the middle of the area, began a volume at 17:23 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 10%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
14 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 27, 10:48 AM MST | Severe Thunderstorm Warning | SLC | Garfield, Kane | 27 min |
| Sep 27, 11:34 AM MST | Severe Thunderstorm Warning | FGZ | Yavapai | 26 min |
| Sep 27, 12:11 PM MST | Severe Thunderstorm Warning | PSR | La Paz, Maricopa | 34 min |
| Sep 27, 12:42 PM MST | Severe Thunderstorm Warning | PSR | Maricopa | 33 min |
| Sep 27, 12:44 PM MST | Severe Thunderstorm Warning | FGZ | Coconino, Yavapai | 9 min |
| Sep 27, 1:06 PM MST | Severe Thunderstorm Warning | FGZ | Coconino, Yavapai | 24 min |
| Sep 27, 1:44 PM MST | Severe Thunderstorm Warning | PSR | Maricopa, Pinal | 46 min |
| Sep 27, 1:50 PM MST | Severe Thunderstorm Warning | FGZ | Yavapai | 25 min |
| Sep 27, 2:08 PM MST | Severe Thunderstorm Warning | PSR | Maricopa, Pinal | 52 min |
| Sep 27, 2:16 PM MST | Severe Thunderstorm Warning | FGZ | Yavapai | 29 min |
| Sep 27, 3:29 PM MST | Flash Flood Warning | PSR | Maricopa, Pinal | 3 hr |
| Sep 27, 4:05 PM MST | Severe Thunderstorm Warning | PSR | Pinal | 25 min |
| Sep 27, 5:33 PM MST | Severe Thunderstorm Warning | FGZ | Gila, Navajo | 27 min |
| Sep 27, 5:42 PM MST | Flash Flood Warning | PSR | Gila, Maricopa, Pinal | 2 hr |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 5.4 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
- 699 J/kg
- Mixed-layer CIN
- -4 J/kg
- Mixed-layer LCL
- 686 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 77 m²/s²
- 0-3 km storm-relative helicity
- 60 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.3
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 26, 9:34 PM MST | Mesoscale Discussion | SPC | Mohave | 2 hr |
| Sep 27, 1:44 AM MST | Mesoscale Discussion | SPC | Mohave | 2 hr |
| Sep 27, 3:16 AM MST | Severe Thunderstorm Watch | SPC | Coconino, Mohave, Yavapai | 8 hr |
| Sep 27, 7:12 AM MST | Mesoscale Discussion | SPC | Coconino, Mohave, Yavapai | 2 hr |
| Sep 27, 9:53 AM MST | Mesoscale Discussion | SPC | Coconino, Maricopa, Yavapai | 67 min |
| Sep 27, 1:40 PM MST | Mesoscale Discussion | SPC | Coconino, Gila, Maricopa, Navajo, Pinal, Yavapai | 2 hr |
| Sep 27, 4:08 PM MST | Mesoscale Discussion | SPC | Gila, Graham, Navajo, Pinal | 2 hr |
Nearby
Severe Thunderstorm Watches in Arizona, 2014Severe Thunderstorm Watches in Utah, 2014Every severe thunderstorm watch in 2014
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.